Harare: Zimbabwe opposition leader Morgan Tsvangirai said on Tuesday that an "important" UN Security Council ruling placed the blame for violence against the opposition with President Robert Mugabe's leadership.

The UN body condemned the violence and said it made a free and fair presidential election run-off impossible.

Tsvangirai, leader of the opposition Movement for Democratic Change, has pulled out of the run-off, scheduled for Friday.

"I think it's a very important resolution," Tsvangirai told Dutch public broadcaster Radio 1.

"It recognises the people who are accountable for the violence, and it squarely placed that responsibility at Mugabe's leadership. I am sure that he can no longer remain defiant to that international position."

He repeated that he would not be participating in the election. "It's ridiculous to go into an election of that kind. It's a one-man competition," Tsvangirai said.

The MDC leader said he had only taken "temporary refuge" in the Dutch embassy in Harare.

"The ambassador has talked to the government and has been assured that there is no threat to me. So from today or tomorrow, I'll be able to make those arrangements," he said.

"I hope that they mean what they say. This is a regime which is acting irrationally."