U.S. Secretary of State Hillary Clinton visits Burma this week, the first trip there by a U.S. secretary of state in more than 50 years.

Clinton departs Monday for Asia, first stopping in South Korea before traveling on to Burma. Her visit to the isolated country begins Wednesday.

A group of 12 human rights organizations wrote to Clinton Monday asking her to take advantage of Burma's interest in a better relationship with the United States. They called on Clinton to intensify calls for Burma's government to release all political prisoners, have meaningful dialogue with the opposition, and end violence in the country. They warned that Burma's recent moves towards democratic reforms are easily reversible.

U.S. President Barack Obama announced earlier this month he was sending Clinton to Burma, saying the U.S. is responding to what he called “flickers of progress” from the Burmese government, which ended decades of military rule in March when it brought in a civilian parliament.

A Burmese presidential aide tells VOA recent developments in diplomatic ties could lead to the end of U.S. sanctions against Burma. The aide cited exchanges of visits by officials from both countries.

Mr. Obama mentioned steps by Burma to open a dialogue with opposition leader Aung San Suu Kyi, the release of some political prisoners and the opening of the political environment. He said that if the country continues to travel down the road of democratic reform, it can forge a new relationship with Washington. But he warned of continued sanctions if Burma fails to move down the path of reform.

He said Secretary Clinton will explore what the U.S. can do to support progress on political reform, human rights and national reconciliation.

Mr. Obama cautioned that despite the apparent progress, Burma will need to go further with reforms. He cited ongoing concerns about Burma's closed political system, its treatment of minorities, its holding of political prisoners and relationship with North Korea.

Mr. Obama's recent announcement, which he made during a visit to Bali, was the most significant U.S. policy move on Burma in years. The U.S. and other western nations have for decades imposed sanctions on the country for its human rights abuses and failure to enact democratic reforms.