Burma has agreed to allow "all aid workers" to stage a relief effort for cyclone survivors, UN chief Ban Ki-moon said after meeting junta leader Than Shwe in Naypyidaw on Friday.

"He has agreed to allow all aid workers regardless of nationalities," Ban told reporters after meeting with the senior general for more than two hours.

Than Shwe also agreed to allow Rangoon airport to be used as an international hub for aid distribution, Ban said.

Than Shwe, who refused to take Ban's phone calls after Cyclone Nargis hit three weeks ago, had previously refused to allow foreign aid workers to stage a full-scale relief effort after the storm left 133,000 dead or missing.

The two leaders met at a modern complex in the junta's purpose-built capital of Naypyidaw in central Burma, where Than Shwe rules in almost complete isolation from a secret bunker that few outsiders have ever seen. The military has ruled as Burma, for nearly 50 years.

Ban is the most senior foreign leader to visit the new capital, where Than Shwe abruptly relocated the entire government in late 2005.

Cautious response

The German government was cautious in its response to the announcement, stressing it was also crucial that aid workers will would guaranteed free movement within the country.

"Even though there are indications that the country is opening up to international aid, the main challenge remains to reach the worst-hit areas quickly and professionally," said Germany's deputy foreign minister Gernot Erler, on Friday in Berlin.

"At the donor-pledging conference [in Rangoon on Sunday], Berlin will make sure this does merely remain a promise and that aid workers really do reach those who need them."

Erler is set to travel to the conference with 10 tons of aid, followed by a further plane organized by Maltese International next week.

Restrictions

The official toll is nearly 134,000 people dead or missing, making Nargis one of the worst cyclones to hit Asia.

Three weeks after the disaster, aid is still only trickling in to the delta due to the junta's restrictions on foreign relief operations.

The junta has accepted relief flights into Yangon from many countries, including the US, its fiercest critic, but has largely kept Western disaster experts out of the delta.

Medical teams from India, China, Thailand, Laos and Bangladesh are working in the delta along with thousands of local medics and other volunteers, state media said.