YANGON, March 4 (CNA) - At least 38 people died on Wednesday (Mar 3) in the "bloodiest" day of Myanmar's crisis, the United Nations said, as the military government defied growing international condemnation of its coup with a violent crackdown that the US said left it "appalled and revulsed".

Myanmar has been in turmoil since Feb 1 when the military ousted and detained civilian leader Aung San Suu Kyi, ending the nation's decade-long experiment with democracy and sparking daily mass protests.

International pressure is mounting: Western powers have repeatedly hit the generals with sanctions, Britain has called for a United Nations Security Council meeting on Friday, and after Wednesday's deaths the United States said it was considering further action.

But the military government has so far ignored the global condemnation, responding to the uprising with escalating strength.

"Only today, 38 people died," UN envoy to Myanmar Christine Schraner Burgener told reporters on Wednesday, adding that more than 50 people had died in total since the military takeover, with many more wounded.

"Today was the bloodiest day since the coup happened," she noted, without providing any further details, including a breakdown of the deaths.

She called for the UN to take "very strong measures" against the generals, adding that in her conversations with them they had dismissed the threat of sanctions.

"I will keep going on, we will not give up," she said.

The violence left the United States "appalled and revulsed", State Department spokesman Ned Price said, telling reporters: "We call on all countries to speak with one voice to condemn the brutal violence by the Burmese military against its own people."