U.S. Secretary of State John Kerry warned Burmese leaders Saturday against backsliding on advances made in human rights.
Kerry was in Myanmar, also known as Burma, for talks with President Thein Sein and the ASEAN foreign ministers' meeting.
A State Department official said Kerry urged Burmese leaders to keep moving forward on constitutional reform leading up to next year's elections.
They also discussed the arrests of journalists and violence and discrimination against the Rohingya Muslims minority.
A State Department official said President Thein was open to talking about all issues Kerry raised.
Later, Kerry said it is impossible not to be impressed by the steps Myanmar's government has taken towards reform and transitioning from a military government.
He said former military officers sit in parliament next to Nobel prize winning opposition leader Aung San Suu Kyi.
Kerry said the Burmese people have the support and friendship of the United States.
The United States eased sanctions on Myanmar and has given more than $200 million in aid since it began moving from a military to a democratic government in 2011.
But Obama administration officials have expressed concern that the arrests of journalists and violence against the Muslims are signs Myanmar may be sliding backwards.
Some information for this report comes from AP and Reuters.