The call came a week after Myanmar's generals conducted a coup in the country.

"The United Kingdom would like to inform all colleagues that together with the European Union, we have submitted a request for a special session on the human rights implications of the crisis in Myanmar," Julian Braithwaite, Britain's ambassador in Geneva, told a council organisational meeting.

Myanmar's military last week detained civilian leader Aung San Suu Kyi and dozens of other members of her National League for Democracy party, ending a decade of civilian rule and triggering international condemnation.

Braithwaite said the call was "in response to the state of emergency imposed in Myanmar, the arbitrary detention of democratically-elected politicians and civil society by the military," which he said had "grave implications for human rights in the country".

"We must respond urgently to the plight of the people of Myanmar and the rapidly deteriorating human rights situation there," he said.

Braithwaite said backers of the special session call would inform other council members soon about the drafting of a resolution on the issue.

He said the motion had the support of an additional 19 of the council's 47 members.

That means in principle that the request would fulfil the requirement for the backing of at least a third of the council's members.

A special session is thereby expected to take place prior to the next regular council session, which kicks off on February 22.

Britain's Foreign Secretary Dominic Raab tweeted Monday that the session should be held this coming Thursday.

The Human Rights Council could not immediately confirm that.