A brutal multi-sided conflict has engulfed Myanmar since 2021, when Min Aung Hlaing's military wrested power from the civilian government of Aung San Suu Kyi.

Following reports of sporadic clashes even after last Friday's quake that has killed more than 3,000 people, the junta joined its opponents on Wednesday in calling a temporary halt to hostilities for relief to be delivered.

But the United Nations rights office has received reports of more than 60 attacks carried out by the military since the earthquake.

"And there have been 16 reports, credible reports, of airstrikes ongoing in different parts of the country, including areas impacted by the earthquakes, since the ceasefire went into effect on April 2," James Rodehaver, head of the rights office's Myanmar team told reporters in Geneva, speaking from Bangkok.

Just moments before, rights office spokeswoman Ravina Shamdasani told reporters the number of reported attacks was 14, but Rodehaver said the office had received "two more such attacks" since the briefing began.

UN rights chief Volker Turk meanwhile insisted in a statement that the announced truce must be followed by immediate and unrestricted access by rescue and humanitarian workers to all those in need.

"I urge a halt to all military operations, and for the focus to be on assisting those impacted by the quake, as well as ensuring unhindered access to humanitarian organisations that are ready to support," he said.

"I hope this terrible tragedy can be a turning point for the country towards an inclusive political solution."