08/09/2015 09:15 BST | Updated 08/09/2016 06:12 BST

Sam Smith Sings New James Bond Theme Song

Brit-award winning singer Sam Smith has been confirmed as the voice of the new Bond theme song.

The 23-year-old said singing the title song to Spectre, starring Daniel Craig as James Bond, was "one of the highlights of my career".

Smith told Radio 1's Nick Grimshaw: "I'm so relieved to actually talk about this, this has been a top secret mission of my own."

He added: "I got called into the office with [producer] Barbara Broccoli and [director] Sam Mendes and they gave me the script, I read the script... they said 'have a go at the song'.

"It's the quickest I've ever written a song - it took 20 minutes... and they loved it!"

The In The Lonely Hour star revealed he recorded the track back in January but has been sworn to secrecy.

Just last week, Smith denied he was working on the project to BBC Radio 2's Jo Whiley.

Yesterday he teased fans by posting a picture on Twitter of a ring on his finger, featuring the symbol of an octopus with blade-like tentacles, the symbol of the Spectre organisation from the 007 universe.

He has now tweeted: "This is one of the highlights of my career. I am honoured to finally announce that I will be singing the next Bond theme song.

"I am so excited to be a part of this iconic British legacy and join an incredible line up of some of my biggest musical inspirations.

"I hope you all enjoy the song as much as I enjoyed making it."

It is the first James Bond theme song recorded by a British male solo artist since 1965, when Sir Tom Jones released Thunderball.

The song - co-written by Jimmy Napes, who worked with Smith on his number one hits Stay With Me and La La La - will be unveiled on September 25.

Spectre, thought to be Craig's final outing as Bond and starring Christoph Waltz as the lead villain, will be released in the UK on October 26.

The title of Smith's new track will be Writing's On The Wall.

Young British star Adele wrote and performed the last Bond theme, Skyfall, which went on to win a string of accolades, including an Oscar, a Grammy and a Golden Globe.

It entered the UK charts at number four, and rose to the number two spot after 14 days, tying with Duran Duran's A View To A Kill as the highest charting Bond theme song ever.