YANGON, Myanmar — After weeks of international pressure, Myanmar agreed to let in medical teams from neighboring countries and give the Association of Southeast Asian Nations some oversight of foreign aid distribution, the regional bloc announced Monday.

The junta continued to bar foreign U.N. staff from the devastated Irawaddy delta even as it bowed to criticism of its refusal to accept foreign assistance. The U.N. said after a brief tour of the delta by its humanitarian chief that conditions there were "terrible," with hundreds of thousands of cyclone victims suffering from hunger, disease and lack of shelter.

Myanmar said it will open its doors to teams from the 10 countries of the Association of Southeast Asian Nations, Singapore Foreign Minister George Yeo told reporters after an emergency meeting of ASEAN foreign ministers in Singapore.

Myanmar Foreign Minister Nyan Win also agreed to participate in an ASEAN-led task force for redistributing foreign aid, Yeo said.

"This mechanism will facilitate the effective distribution and utilization of assistance from the international community, including the expeditious and effective deployment of relief workers, especially health and medical personnel," Yeo told a news conference.

Myanmar officials did not comment on the announcement.

The bloc will work with the U.N. to hold an aid donor conference in Yangon on May 25, Yeo said.

The junta announced a three-day mourning period for cyclone victims starting Tuesday. Inside Myanmar, people are angry at the pace of the government effort following the storm that left at least 130,000 people dead or missing.

China began three days of mourning Monday for the more than 32,000 dead from an earthquake in Sichuan province last week.

Myanmar's military regime also allowed the U.N. humanitarian chief into the Irrawaddy delta for a brief tour Monday, a U.N. official said.

John Holmes, the U.N. undersecretary-general for humanitarian affairs, flew by helicopter to the delta before returning to Myanmar's largest city, Yangon, to meet with international aid agencies, said a U.N. official who spoke on condition of anonymity because he was not authorized to speak with the media.

Others, including U.N. Secretary-General Ban Ki-moon, also will be allowed into the disaster zone this week.

An Asian diplomat said Myanmar has invited at least three representatives of several countries to tour the delta Friday. He spoke on condition of anonymity because the news has not been made public.

Ban is to travel to the delta after his scheduled arrival in the country Wednesday, U.N. spokeswoman Michele Montas said in New York.