Elton John and Mary J. Blige will perform a duet at his post-Oscars party.

The superstar singers will take to the stage at Elton's annual AIDS Foundation bash after the Academy Awards ceremony on Sunday.

Blige said: "Elton John is one of the most inspirational musicians and philanthropists in this industry for me."

"I respect him with all my heart and it is truly a pleasure to be performing with him on such an important night as we look to raise awareness and vital funds for the fight against HIV and AIDS."

This is not the first time the pair have collaborated. In 1999, Elton played the piano on the 37-year-old star's single 'Deep Inside'.

Elton's annual Oscar party has raised more than $15 million for his charity over the past 15 years. Mary is also a keen campaigner for AIDS awareness, and in 2000 she fronted MAC Cosmetics' Viva Glam campaign.

Meanwhile, it has been reported John Travolta will perform a dance routine at the 80th Academy Awards at Los Angeles' Kodak Theater on Sunday.

A source said: "As singer Jon McLaughlin performs the Oscar-nominated 'So Close' from 'Enchanted' with 30 or so dancers, Travolta will appear. He is going to grab one of the dancers and dance his way to the podium and then present the award for Best Original Song."