The talks come as the Obama administration dismantles longstanding sanctions to reward Myanmar's leaders for political and economic reforms.

"The results of the dialogue were assessed to be very positive and we look forward to continuing these discussions with Burmese authorities," State Department spokeswoman Victoria Nuland told a news briefing.

"We weren't sure whether the Burmese would be open to addressing all of those issues, and they were," Nuland said.

"We are confident that we have now an open channel with the government of Burma to discuss human rights and to continue to work on bringing them where they want to be in terms of human rights standards for their government."

The U.S. delegation also included Deputy Assistant Secretary of Defense Vikram Singh and other U.S. military officials, a signal that the Pentagon also is watching closely as Myanmar begins moving out of the shadow of China, long its chief regional ally.

RAPID CHANGES

The United States has seen ties warm rapidly with Myanmar since a quasi-civilian government took office there in March 2011, ending five decades of military rule.

The new government has launched rapid reforms, including an overhaul of the economy, an easing of censorship, the legalization of trade unions and protests, and the freeing of political prisoners.

The United States has responded with diplomatic and economic gestures, sending Secretary of State Hillary Clinton to Myanmar last year and easing sanctions.

Myanmar released its latest group of political prisoners last month, just before Myanmar President Thein Sein and veteran pro-democracy leader Aung San Suu Kyi visited the United States on separate trips.

"We have all spoken out about the need to get to zero in terms of political prisoners and we're continuing to work with the government of Burma on that," Nuland said.

The United States has also expressed concern over ongoing fighting with ethnic minority groups and violence against ethnic Rohingya Muslims in Myanmar's western Rakhine state, as well as the government's continued military ties with North Korea.

Activists say the United States has pressed Myanmar consistently on human rights but warn that a surge in economic and other ties could may push the issue down the priority list.

"The simple fact is that U.S. policy toward Burma is no longer just about human rights," said John Sifton, Asia advocacy director at Human Rights Watch.

"Now human rights is just another sector that is part of the dialogue and there are other folks at the table, from the military to the business community, who have their own wish lists. As a result it is that much harder to focus the pressure."

(Reporting by Andrew Quinn; Editing by David Brunnstrom)