Rain adds to challenge for Myanmar quake relief

Rain is falling on earthquake-hit Myanmar, which aid agencies fear will complicate relief efforts and raise the risk of disease as the United Nations says more tents are needed to shelter the homeless.

The death toll from the powerful quake that hit on March 28 has risen to 3471, state media reported on Sunday, with 4671 people injured and another 214 still missing.

Aid agencies are warning the combination of the unseasonable rains and extreme heat could cause outbreaks of disease, including cholera, among quake survivors who are camping in the open.

"Families sleeping outside the ruins of their homes while bodies of loved ones are pulled from rubble. Real fear of more quakes," visiting UN aid chief Tom Fletcher said in a post on X.

"We need to get tents and hope to survivors as they rebuild their shattered lives," he said, adding strong, co-ordinated action was the key to saving as many lives as possible.

Myanmar's neighbours China, India and other Southeast Asian nations have dispatched relief supplies and rescuers over the past week to aid the recovery effort in quake-hit areas that are home to about 28 million people.

The US, which was until recently the world's top humanitarian donor, has pledged at least $US9 million ($A15 million) to Myanmar to support earthquake-affected communities but officials say the dismantling of the US foreign aid program has affected its response.

Three US Agency for International Development workers who travelled to Myanmar after the quake were told they were being let go, Marcia Wong, a former senior USAID official, told Reuters.

"This team is working incredibly hard, focused on getting humanitarian aid to those in need. To get news of your imminent termination - how can that not be demoralising?" Wong said.

In Thailand, authorities said the nation's death toll from the quake had risen to 24.

Of those, 17 died at the site of a skyscraper in the capital, Bangkok, that collapsed while under construction. A further 77 were still missing there.

Myanmar's military has struggled to run the country since overthrowing the government of Nobel laureate Aung San Suu Kyi in 2021, leaving the economy and basic services, including healthcare, in tatters.

The civil war that followed has displaced more than three million people, with widespread food insecurity and more than a third of the population in need of humanitarian assistance, the UN says.

A ceasefire was declared on Wednesday but the UN Office of the High Commissioner for Human Rights said on Friday the junta was restricting aid in areas that did not back its rule. It also said it was investigating reported attacks by the junta against opponents, including after the ceasefire.

Free Burma Rangers, a relief group, told Reuters on Saturday that the military had dropped bombs in Karenni and Shan states on Thursday and Friday despite the ceasefire announcement, killing at least five people.