Bono was referring to what he sees as Martin's failure to meet a pledge to boost the country's commitment to foreign aid. The singer's personal cause is campaigning to alleviate debt and poverty in the developing world.

In the interview on CBC radio Bono said, "We were looking for Canada to lead rather than be a laggard," adding that it felt like "business as usual."

"This is no time to just turn inward. I know there are problems here at home. But don't lose your focus, Prime Minister, on how history will remember this moment," Bono challenged.

At one point in the broadcast, Bono read out the number of Martin's office on Canadian radio, urging listeners to call him.

In 2003, Bono was praising the new leader's pledge to increase foreign aid. "I'm going to be the biggest pain in the ass," the musician warned at the time.

Meanwhile, Martin is facing a fight to save his minority government, recently undermined by a financial scandal.

Editor's note:
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