Burma plays host this week to senior U.N. and U.S. diplomats amid mounting interest in that nation's cautious moves toward democratic reform.

Vijay Nambiar, chief of staff to U.N. Secretary-General Ban Ki-moon, arrived in the Burmese capital Monday for a five-day visit that will include talks with senior government officials.

U.S. Assistant Secretary of State Michael Posner was due in the country Tuesday, to be joined Wednesday by Derek Mitchell, the U.S. policy coordinator for Burma.

All the officials say they expect to hold meetings with leaders of civil society as well as government officials.

Foreign diplomats are encouraging the Burmese government to continue and expand reforms that have been under way since a new, nominally civilian government took office at the end of March.

Government officials have permitted visits by human rights monitors, opened a dialogue with some of their critics including pro-democracy campaigner Aung San Suu Kyi, and eased the nation's strict press censorship.

The latest in a series of meetings between Aung San Suu Kyi and Labor Minister Aung Kyi took place on Sunday.

However, human rights groups and Western governments say Burma must release about 2,000 political prisoners before international sanctions can be lifted.