Hillary Clinton is holding landmark talks with members of Myanmar's government, on the first high-level visit by a US official in half a century.
Myanmar President Thein Sein hailed a "new chapter in relations" with Washington as the two set down for talks at the presidential palace in the capital, Naypyidaw.
"This visit is the first in five decades. Your visit is historic and will be a new chapter in relations. I appreciate the atmosphere you have created for friendly relations," he told Clinton.
Clinton, in turn, told the former general: "I am here today because President [Barack] Obama and myself are encouraged by the steps that you and your government have taken to provide for your people."
Speaking in South Korea on Wednesday, before her departure, Clinton said she was hopeful that "flickers of progress" in Myanmar will "be ignited into a movement for change."
US officials have said Clinton will raise concerns about Myanmar's suspected military links with North Korea during her talks.
It is unlikely that she will announce any major changes in US policy towards Myanmar, though she may offer symbolic steps, like upgrading the US mission there to a full embassy.
Myanmar was ruled by the military for decades until elections last year brought a nominally civilian government to power - albeit one with close links to the army.
"This redistribution of power has seen many surprises come up and the pace of reform has been much quicker than many had anticipated," Al Jazeera's Aela Calla, reporting from Naypyidaw, said.
"President Thein Sein and also the speaker of the lower house have shown great desire to open the country to the West. In particular, they will be looking for help to reform the economy. A third of Myanmar is still in poverty and foreign aid is low."
Rights record improved
The country's rulers abruptly moved the capital to Naypyidaw from Yangon in 2005.
Clinton will travel to the former capital later on Thursday, where she will meet opposition leader Aung San Suu Kyi, the head of the National League for Democracy and a Nobel laureate who has spent much of the last two decades in prison.
|Thein Sein, right, was Myanmar's prime minister before he became the president in March this year [Reuters]
The UN and international human rights organisations have repeatedly issued reports of widespread and systematic human rights violations in Myanmar. But since the transition to "civilian" government, the country's record has been improving, rights groups say.
The government recently released more than 230 political prisoners, eased media censorship and sought guidance from international financial institutions to revive its economy.
Myanmar also amended its political parties law, removing a clause which bars anyone convicted of a crime from joining a party or taking part in an election. That paves the way for political prisoners, particularly Suu Kyi, to run for office.
In a rare interview with US reporters on Wednesday, Suu Kyi said she was ready to gamble that recent reforms represent a genuine transition to democracy after decades of false hopes.
"We hope that they are meaningful," she said. "I think we have to be prepared to take risk. Nothing is guaranteed."
China called on Thursday for international sanctions against its key ally Myanmar to be lifted.
"We maintain relevant nations should lift sanctions on Myanmar and promote Myanmar's stability," Chinese foreign ministry spokesman Hong Lei said.
Clinton has said credible elections are a prerequisite for ending US sanctions, along with the release of more political prisoners and peace with ethnic minorities.