Children who survived the cyclone huddle together in Dedaye township in Burma's badly damaged Irrawaddy Delta earlier this week. (UNICEF/Associated Press)

Burma has promised the United Nations that it will allow all foreign aid workers to enter its borders, almost three weeks after a deadly cyclone ravaged the southeast country and left an estimated 2.5 million people struggling to survive.

But Burma's ruling military junta said it will still refuse entry to U.S., British and French warships wanting to unload relief supplies at Burmese ports, said UN Secretary General Ban Ki-moon.

Ban announced Burma's decision to loosen some of its restrictions after holding a two-hour meeting with the leader of Burma's military government Friday.

"I had a very good meeting with senior Gen. Than Shwe," Ban said in the Burmese administrative capital of Naypyidaw. "He has agreed to allow all the aid workers, regardless of nationality, [into Burma]."

UN Secretary General Ban Ki-moon, left, got assurances Friday from Burmese leader Gen. Than Shwe, right, that all aid workers will be allowed into Burma. (Stan Honda/Associated Press)

Cyclone Nargis, which hit on May 3, left 134,000 people dead or missing, while those who survived are struggling to find food and shelter, and are at risk of disease. Many survivors have lost their homes and farms in the widespread flooding and monsoon rains.

The UN has estimated that only 25 per cent of those in need have been getting help so far.

Canada announced Friday it will deliver an additional $12 million in aid to Burma. International Co-operation Minister Bev Oda said the money will help the UN, Canadian and international relief agencies provide food, medicine and basic supplies to cyclone victims.

Earlier this month, Canada committed $2 million to the aid effort and said it would match donations made by Canadians to the Burma Cyclone Relief Fund.

'This is a significant step forward'

Some aid workers welcomed the news of Burma's loosening of entry restrictions, saying there is only a narrow window of opportunity to help those in need.

"This is a significant step forward and could be a turning point in the aid response," said Brian Agland, who works with the charity CARE in Burma. "We welcome the agreement."

Others were more skeptical. U.S. State Department spokesman Tom Casey said he will wait and see whether Burma actually follows through.

"Seeing is believing," he said, noting that the U.S. will test the announcement by reapplying for visas for U.S. crisis workers currently waiting for paperwork in Thailand.

Opening access to the ravaged delta

Burma has turned back many aid workers, particularly from Western countries like the United States, which has a history of strained relations with Burma. The few aid workers allowed in were mostly restricted to working in the city of Rangoon, and were denied access to the hardest hit region — the Irrawaddy Delta.

Ban said Burma's military leader assured him foreigners would now be given "unhindered access to affected areas."

"I urged him that it would be crucially important for him to allow [in] aid workers as swiftly as possible, and all these aid relief items also be delivered to the needy people as soon as possible," he said.

Ban arrived in Naypyidaw Friday after touring the some of areas devastated by the cyclone on Thursday, including a makeshift relief camp in the village of Kyondah where 500 people were living in small blue tents. Ban said the experience was very upsetting.

With files from the Associated Press