Madonna has asked Justin Timberlake and Britney Spears to perform together during the finale of her upcoming world tour, it's been reported.

The pop star, who begins her Sticky & Sweet tour in Cardiff next month, is understood to be keen to team up with both singers, who used to date each other, on stage.

Spears spokesperson has already confirmed that the singer is to shot a promo video for Madonna's tour, which will be shown during the show.

But Madonna now wants Timberlake to join her in person, according to the Sun newspaper.

“Madonna is always trying to raise the bar and Britney and Timberlake on the same stage would be perfect,” a source told the newspaper.

“They have both been asked but I think both are a bit reluctant. Britney would find it all a bit emotional and JT might not fancy it. More likely is that they both appear on different dates.

"But if anyone can make this happen it’s Madonna.”

Timberlake makes a guest appearance on Madonna's latest album 'Hard Candy' and performed with her during a secret show in New York earlier this year.

(by Jason Gregory)