The couple have decided to end their relationship just five months after getting engaged.
"After careful consideration, we have decided to amicably end our relationship," they said in a statement to Mail Online.
"In the interests of our family we remain good friends and we hope that people will respect our privacy at this time."
The pair first got together in 2013 when their respective bands both appeared on ‘The Big Reunion’.
Natasha has three other children Josh, 13, Harry, 10 and four-year-old Alfie, from previous relationships, and was married to ex-husband Riad Erraji for six years before their split in July 2013.
Ritchie and Natasha had previously spoken of their plans to wed in 2017, after he proposed during a romantic trip to Rome last October.
Speaking about the moment he got down on one knee, she told OK! magazine: "It was so romantic and it couldn't have been more perfect. I felt overwhelmed and like I was in a movie.
"We were sobbing as I said 'Yes!'"
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