U2 frontman Bono seized the opportunity to do an impression of former US President Bill Clinton during the recent Clinton Global Initiative.

During his impression, Bono said: "When I first met Bono, he walked to the Oval office and I actually thought it was a member of his own road crew.

"He wasn't really dressed right. I felt like the rockstar on that occasion. But together, you know, we did this drop the debt thing."

Mr Clinton returned the favour by imitating Bono during a taping of CNN's Piers Morgan Tonight.

The Clinton Global Initiative brings together heads of state, CEOs, philanthropists and others to help find solutions to the world's major problems.