WASHINGTON: The United States has welcomed the release of an American detained in Myanmar but called on the regime to free all political prisoners including democracy icon Aung San Suu Kyi as it reviews its policy.

American John Yettaw, jailed over a bizarre incident in which he swam to the Nobel laureate's home, flew out of Myanmar on Sunday after US Senator Jim Webb secured his release from the reclusive military junta.

The White House said President Barack Obama was "pleased" by Yettaw's release in Myanmar, earlier known as Burma.

"He appreciates this decision by the Burmese government," a White House statement said.

"We urge the Burmese leadership in this spirit to release all the political prisoners it is holding in detention or in house arrest, including Aung San Suu Kyi," the White House said.

Yettaw's eccentric behavior landed Aung San Suu Kyi with a further sentence for violating terms of her house arrest. She has been confined for most of the past two decades since her party swept elections but never allowed into power.

Webb, a member of Obama's Democratic Party who advocates engaging the junta, held unprecedented talks with Myanmar's leader Than Shwe and also a rare meeting with Aung San Suu Kyi.

Webb was hopeful for a breakthrough with the isolated regime.

"I think we have a moment where we might be able to do something," he told CNN, speaking from Bangkok.

He said he made clear to Than Shwe that rare elections called for next year would have no legitimacy unless Aung San Suu Kyi is able to participate.

He said that the Association of Southeast Asian Nations (ASEAN), a 10-member bloc including Myanmar, may issue a petition seeking an amnesty for Aung San Suu Kyi, "which would be a major step forward in resolving the situation."

ASEAN has frequently faced Western criticism for being weak-kneed on Myanmar, supporting a policy of engagement with the regime while the United States and European Union maintain sanctions.

The Obama administration, which has been skeptical of sanctions as a diplomatic tool, is conducting a review of Myanmar policy.

While the administration has previously indicated that it was not considering lifting sanctions, Webb said Aung San Suu Kyi -- long supportive of such tough measures -- was not opposed to easing some restrictions.

A senior administration official, speaking on condition of anonymity, said the United States was eager to hear more about Aung San Suu Kyi's opinions.

"Obviously if Aung San Suu Kyi has views on how we should proceed, we will listen closely to what she tells us," the official said.

But State Department spokesman P.J. Crowley said Myanmar needed to do more to return to US good graces.

"We'll be looking for signs that Burma's fundamentally changing its approach and its policies. I don't think that Mr. Yettaw's release is an indication of that," Crowley told reporters.

Secretary of State Hillary Clinton spoke with Webb by telephone on Sunday and plans more extensive talks with him once he returns, officials said.

The initiative by Webb, who heads the Senate Foreign Relations subcommittee on Asia, has angered many activists working on Myanmar who fear he is giving the junta a rare opportunity to appear in a favorable light.

Leonard Leo, chair of the US Commission on Religious Freedom, a government advisory board, said that the administration should "pursue a dual strategy of more sanctions and more engagement."

"Burma?s military leaders will continue their repressive ways unless diplomatic efforts are coordinated, targeted and tough," he said.