US soldier Bradley Manning has become a woman called Chelsea.

The 25-year-old, who has been sentenced to 35 years in prison for leaking classified documents to WikiLeaks, revealed the plans in a statement to NBC.

"I am Chelsea Manning," Manning said.

"I am a female."

chelsea manning

Manning dressed as a woman in 2010

"Given the way that I feel and have felt since childhood, I want to begin hormone therapy as soon as possible," Manning said.

"I also request that starting today you refer to me by my new name and use the feminine pronoun."

The statement was signed Chelsea E. Manning.

The soldier's struggles with identity were key to his defence in his court martial, the BBC reported.

His team said the army missed warning signs that he was struggling with gender identity issues, such as when he sent bosses an email saying he wanted to be a woman, with a photograph of himself wearing makeup and a blonde wig.

Manning is expected to serve his sentence at the U.S. Disciplinary Barracks at Fort Leavenworth, Kansas.

The soldier's lawyer, David Coombs, has said he could be pardoned in seven years.

Coombs said the prison should "do the right thing" and provide hormone therapy for the soldier:

He added: "If Fort Leavenworth does not, then I'm going to do everything in my power to make sure they are forced to do so."

Wednesday's sentencing ends three years of speculation over the fate of Manning, who for many has become a heroic figure and a symbol of truth and transparency against the clandestine misdeeds of the American administration during the Iraq War.

Critics compared the 35-year term to far shorter sentences handed to US soldiers found guilty of abusing prisoners in Iraq.

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  • Military Judge Sentences Bradley Manning

    FORT MEADE, MD - AUGUST 21: US Army Private First Class Bradley Manning is escorted by military police as he arrives for his sentencing at military court facility for the sentencing phase of his trial on August 21, 2013 in Fort Meade, Maryland. Manning was found guilty of several counts under the Espionage Act, but acquitted of the most serious charge of aiding the enemy. (Photo by Mark Wilson/Getty Images)

  • Bradley Manning

    Army Pfc. Bradley Manning steps out of a security vehicle as he is escorted into a courthouse in Fort Meade, Md., Wednesday, Aug. 21, 2013, before a sentencing hearing in his court martial. The military judge overseeing Manning's trial said she will announce on Wednesday his sentence for giving reams of classified information to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted into a courthouse in Fort Meade, Md., Wednesday, Aug. 21, 2013, before a sentencing hearing in his court martial. The military judge overseeing Manning's trial said she will announce on Wednesday his sentence for giving reams of classified information to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted into a courthouse in Fort Meade, Md., Wednesday, Aug. 21, 2013, before a sentencing hearing in his court martial. The military judge overseeing Manning's trial said she will announce on Wednesday his sentence for giving reams of classified information to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted into a courthouse in Fort Meade, Md., Wednesday, Aug. 21, 2013, before a sentencing hearing in his court martial. The military judge overseeing Manning's trial said she will announce on Wednesday his sentence for giving reams of classified information to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning steps out of a security vehicle as he is escorted into a courthouse in Fort Meade, Md., Wednesday, Aug. 21, 2013, before a sentencing hearing in his court martial. The military judge overseeing Manning's trial said she will announce on Wednesday his sentence for giving reams of classified information to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning wears handcuffs as he is escorted into a courthouse in Fort Meade, Md., Wednesday, Aug. 21, 2013, before a sentencing hearing in his court martial. The military judge overseeing Manning's trial said she will announce on Wednesday his sentence for giving reams of classified information to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted into a courthouse in Fort Meade, Md., Wednesday, Aug. 21, 2013, before a sentencing hearing in his court martial. The military judge overseeing Manning's trial said she will announce on Wednesday his sentence for giving reams of classified information to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted into a courthouse in Fort Meade, Md., Wednesday, Aug. 21, 2013, before a sentencing hearing in his court martial. The military judge overseeing Manning's trial said she will announce on Wednesday his sentence for giving reams of classified information to WikiLeaks. (AP Photo/Patrick Semansky)

  • Military Judge Sentences Bradley Manning

    FORT MEADE, MD - AUGUST 21: US Army Private First Class Bradley Manning (C) is escorted by military police as he arrives for his sentencing at military court facility for the sentencing phase of his trial on August 21, 2013 in Fort Meade, Maryland. Manning was found guilty of several counts under the Espionage Act, but acquitted of the most serious charge of aiding the enemy. (Photo by Mark Wilson/Getty Images)

  • Military Judge Sentences Bradley Manning

    FORT MEADE, MD - AUGUST 21: US Army Private First Class Bradley Manning is escorted by military police as he arrives for his sentencing at military court facility for the sentencing phase of his trial on August 21, 2013 in Fort Meade, Maryland. Manning was found guilty of several counts under the Espionage Act, but acquitted of the most serious charge of aiding the enemy. (Photo by Mark Wilson/Getty Images)

  • Military Judge Sentences Bradley Manning

    FORT MEADE, MD - AUGUST 21: US Army Private First Class Bradley Manning is escorted by military police as he arrives for his sentencing at military court facility for the sentencing phase of his trial on August 21, 2013 in Fort Meade, Maryland. Manning was found guilty of several counts under the Espionage Act, but acquitted of the most serious charge of aiding the enemy. (Photo by Mark Wilson/Getty Images)

  • Military Judge Sentences Bradley Manning

    FORT MEADE, MD - AUGUST 21: US Army Private First Class Bradley Manning is escorted by military police as he arrives for his sentencing at military court facility for the sentencing phase of his trial on August 21, 2013 in Fort Meade, Maryland. Manning was found guilty of several counts under the Espionage Act, but acquitted of the most serious charge of aiding the enemy. (Photo by Mark Wilson/Getty Images)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted to a security vehicle outside a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, after a hearing in his court martial. A U.S. military judge is expected to announce her sentencing decision Wednesday in Manning's role in leaking classified material to WikiLeaks. (AP Photo/Patrick Semansky)

  • Military Judge Sentences Bradley Manning

    FORT MEADE, MD - AUGUST 21: US Army Private First Class Bradley Manning is escorted by military police as he arrives for his sentencing at military court facility for the sentencing phase of his trial August 21, 2013 in Fort Meade, Maryland. Manning was found guilty of several counts under the Espionage Act, but acquitted of the most serious charge of aiding the enemy. (Photo by Mark Wilson/Getty Images)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted to a security vehicle outside a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, after a hearing in his court martial. A U.S. military judge is expected to announce her sentencing decision Wednesday in Manning's role in leaking classified material to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted to a security vehicle outside a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, after a hearing in his court martial. A U.S. military judge is expected to announce her sentencing decision Wednesday in Manning's role in leaking classified material to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning, center, is escorted to a security vehicle outside a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, after a hearing in his court martial. A U.S. military judge is expected to announce her sentencing decision Wednesday in Manning's role in leaking classified material to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning wears handcuffs as he is escorted to a security vehicle outside a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, after a hearing in his court martial. A U.S. military judge is expected to announce her sentencing decision Wednesday in Manning's role in leaking classified material to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted to a security vehicle outside a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, after a hearing in his court martial. A U.S. military judge is expected to announce her sentencing decision Wednesday in Manning's role in leaking classified material to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning steps into a security vehicle outside a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, after a hearing in his court martial. A U.S. military judge is expected to announce her sentencing decision Wednesday in Manning's role in leaking classified material to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted to a security vehicle outside a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, after a hearing in his court martial. A U.S. military judge is expected to announce her sentencing decision Wednesday in Manning's role in leaking classified material to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning, center, is escorted to a security vehicle outside a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, after a hearing in his court martial. A U.S. military judge is expected to announce her sentencing decision Wednesday in Manning's role in leaking classified material to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted into a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, before a hearing in his court martial. A prosecutor recommended in closing arguments Monday that Manning should spend 60 years in prison for giving classified material to WikiLeaks. A U.S. military judge was set to deliberate the sentence of Manning on Tuesday for the largest leak of classified information in the country's history. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning, center, is escorted into a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, before a hearing in his court martial. A prosecutor recommended in closing arguments Monday that Manning should spend 60 years in prison for giving classified material to WikiLeaks. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted into a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, before a hearing in his court martial. A prosecutor recommended in closing arguments Monday that Manning should spend 60 years in prison for giving classified material to WikiLeaks. A U.S. military judge was set to deliberate the sentence of Manning on Tuesday for the largest leak of classified information in the country's history. (AP Photo/Patrick Semansky)

  • Bradley Manning

    Army Pfc. Bradley Manning is escorted from a security vehicle into a courthouse in Fort Meade, Md., Tuesday, Aug. 20, 2013, before a hearing in his court martial. A prosecutor recommended in closing arguments Monday that Manning should spend 60 years in prison for giving classified material to WikiLeaks. A U.S. military judge was set to deliberate the sentence of soldier Bradley Manning on Tuesday for the largest leak of classified information in the country's history. (AP Photo/Patrick Semansky)

  • Sentencing Awaiting In Bradley Manning Trial

    FORT MEADE, MD - AUGUST 20: US Army Private First Class Bradley Manning is escorted out of a military court facility during the sentencing phase of his trial August 20, 2013 in Fort Meade, Maryland. Manning was found guilty of several counts under the Espionage Act, but acquitted of the most serious charge of aiding the enemy. (Photo by Mark Wilson/Getty Images)

  • Sentencing Awaiting In Bradley Manning Trial

    FORT MEADE, MD - AUGUST 20: US Army Private First Class Bradley Manning is escorted out of a military court facilityÊduring the sentencing phase of his trial August 20, 2013 in Fort Meade, Maryland. Manning was found guilty of several counts under the Espionage Act, but acquitted of the most serious charge of aiding the enemy. (Photo by Mark Wilson/Getty Images)

  • Sentencing Awaiting In Bradley Manning Trial

    FORT MEADE, MD - AUGUST 20: US Army Private First Class Bradley Manning is escorted out of a military court facilityÊduring the sentencing phase of his trial August 20, 2013 in Fort Meade, Maryland. Manning was found guilty of several counts under the Espionage Act, but acquitted of the most serious charge of aiding the enemy. (Photo by Mark Wilson/Getty Images)

  • Bradley Manning

    In this July 30, 2013 photo, Army Pfc. Bradley Manning is escorted out of a courthouse in Fort Meade, Md. Few Americans in living memory have emerged from obscurity to become such polarizing public figures _ admired by many around the world, fiercely denigrated by many in his homeland. (AP Photo/Patrick Semansky)

  • Bradley Manning

    In this July 30, 2013 photo, Army Pfc. Bradley Manning is escorted out of a courthouse in Fort Meade, Md. Few Americans in living memory have emerged from obscurity to become such polarizing public figures _ admired by many around the world, fiercely denigrated by many in his homeland. (AP Photo/Patrick Semansky)