Us Weekly magazine reported that Witherspoon already has experience singing after taking voice lessons to prepare her for the role of singer June Carter Cash in 'Walk the Line'.

Witherspoon performed several songs in the 2005 movie - a biopic of Johnny Cash, who was played by Joaquin Phoenix - and won the Best Actress Oscar for her performance.

However, the actress admitted at the time she didn't enjoy the musical parts of the film, describing them as "the most challenging, horrifying experience of [her] life".

She added: "They literally had to push me to get me up there on the stage and say, 'You have to do this. It is time. We are all waiting for you.'

"I thought I was going to throw up the whole first day. It was awful."

It seems Reese - who was three children, Ava, 13, and Deacon, eight, with ex-husband Ryan Phillippe, and newborn son Tennessee James, with her husband Jim Toth - may have had a change of heart about her singing if the collaboration rumours are true.

No details about the project have been confirmed.