NEW YORK - U2 frontman Bono, a leading campaigner for Myanmar's leader Aung San Suu Kyi when she was under house arrest, has called on her to resign over the deadly campaign against Rohingya Muslims.

The singer - who championed Suu Kyi in the 2000 U2 song "Walk On," with fans encouraged to wear masks of the then opposition leader when the band played it live - said he felt "nauseated" by images of the bloodshed and refugee crisis.

"I have genuinely felt ill, because I can't quite believe what the evidence all points to. But there is ethnic cleansing," he told Rolling Stone magazine in its latest issue.

"It really is happening, and she has to step down because she knows it's happening," Bono said,

Pressed on his remarks in the interview conducted by Rolling Stone's founder, Jann Wenner, Bono said: "She should, at the very least, be speaking out more. And if people don't listen, then resign."

The United Nations and the United States have also described Myanmar's campaign against the stateless, mostly Muslim Rohingya people as ethnic cleansing.

Doctors Without Borders said that at least 6,700 Rohingya were killed in the first month of sweeps on villages launched in response to rebel attacks. Another 655,000 Rohingya have fled to neighboring Bangladesh.

Suu Kyi, the winner of the 1991 Nobel Peace Prize, enjoyed wide support from celebrities as she spent most of two decades under house arrest on orders of Myanmar's military junta.

Myanmar's transition to democracy and Suu Kyi's elevation last year to de facto leader initially delighted human rights groups, but they have since been outraged by her reticence in addressing the anti-Rohingya campaign.

Some experts believe Suu Kyi has made a calculated decision not to take the political risks of speaking out as the Rohingya are widely despised in Buddhist-majority Myanmar, and in any case she does not control the military.

Bono said of Suu Kyi's possible reasoning: "Maybe it's that she doesn't want to lose the country back to the military. But she already has, if the pictures are what we go by, anyway."

Earlier this month Dublin, Bono's hometown, revoked a city award given to Suu Kyi to protest her handling of the violence. - AFP