Bono has defended U2's decision to give away their latest album for free - saying it was in the spirit of punk rock.

The band came under fire when they and Apple "gifted" 500 million iTunes users with their new album Songs Of Innocence earlier this month, sparking complaints from users about the record being automatically downloaded onto their Apple products without their permission. Apple even created a tool to allow customers to remove the album in just one click.

But Bono has responded to the criticism on Jo Whiley's BBC Radio 2 show, saying the band had always aimed to "stir things up a bit".

He said: "That's always been the way. It was the same on our first album. That was kind of why you got into a band, to stir things up and annoy people. That's the whole punk rock thing... the only thing that could have gone wrong would have been being ignored."

The Irish singer said 38 million people had listened to the album in the last seven days.

"If you're a songwriter, if you're in a band, that's all you can ask for," he said. "Whether they take them to their heart is something else."

Asked about the backlash he exclaimed: "Oh for God's sakes... Really and truly - we get people who might want to delete it but nobody has deleted more U2 songs in the last five years than U2!"

Bono said that Apple had bought the album as a "gift to give to all their music customers". It is rumoured the computer company may have paid as much as 100 million US dollars (£62 million) for the record.