YANGON, Myanmar - Former New Mexico Gov. Bill Richardson has resigned from an advisory panel on the massive Rohingya refugee crisis, calling it a "whitewash and a cheerleading operation" for Myanmar leader Aung San Suu Kyi.

The sudden resignation Wednesday of probably the panel's most prominent member, a former senior U.S. politician and diplomat who considered Suu Kyi a close friend, raises serious questions about international efforts to deal with the calamitous fallout of Myanmar military operations since August against the Rohingya Muslims that the United Nations has called "textbook ethnic cleansing."

It also offers possible insight into the thinking of Suu Kyi, a Nobel Peace Prize laureate once revered as an icon of human rights whose leadership during the Rohingya crisis has shocked many outsiders.

Richardson, a former U.S. ambassador to the United Nations and President Bill Clinton's energy secretary, castigated Suu Kyi for blaming outsiders for the crisis instead of looking honestly at military actions that have forced nearly 700,000 Rohingya to flee to squalid refugee camps in Bangladesh, where they have spoken of mass killings, rapes and the obliteration of whole villages in Myanmar.

"She believes there's a concerted international effort against Myanmar, and I believe she is wrong," Richardson said Wednesday evening.

The 10-member advisory board is meant to implement earlier Rohingya recommendations made by a group led by former U.N. Secretary-General Kofi Annan, but Richardson said Suu Kyi appears to want the board to validate her Rohingya policies.

"The advisory board is mainly a whitewash and a cheerleading operation for the Myanmar government, and I'm not going to be part of it because I think there are serious issues of human rights violations, safety, citizenship, peace and stability that need to be addressed," Richardson said. "I just felt that my advice and counsel would not be heeded."

A spokesman for Myanmar's government said it was sorry about Richardson's resignation.

"The reason why we formed the advisory commission was because we hoped that the team will give us constructive support and advice," spokesman Zaw Htay said in Naypyitaw. "We are sorry that Bill Richardson is releasing a statement and resigned from the commission but that, of course, is out of our control."

In Washington, U.S. State Department spokeswoman Heather Nauert said Richardson's resignation and his reasons for doing so "are cause for concern."