I’ll Stand By You – Sarah’s Version premiered on Wednesday during Zoe Ball’s BBC Radio 2 breakfast show.
Speaking on the programme, Nadine called the song “really special” and paid tribute to “our wonderful Sarah”.
The new mix showcases the singer’s strength as a vocalist – with a tell-tale rasp that catches on the song’s message of friendship and solidarity.
A new version of the music video, featuring unseen archive footage, will also be screened during the Children in Need appeal show on BBC One on 15 November. The single will be released on the same day.
The Pretenders star Chrissie Hynde, who wrote and released the original song in 1994, endorsed the new recording.
“How wonderful to hear I’ll Stand By You with the lovely vocals of Sarah Harding leading the way for BBC Children in Need,” she said in a press release.
Children in Need is the BBC’s charity for disadvantaged children and young people across the UK.
Meanwhile, ITV will screen highlights of the recent Girls Aloud tour on 17 November, marking what would have been Harding’s 43rd birthday.
The full concert will also be available to stream on ITVX.