BAGHDAD/UNITED NATIONS (Reuters) - Iraq's new government told the United Nations it wanted the right to decide on the future presence of U.S.-led forces and other security issues but in general sided with Washington.

Foreign Minister Hoshiyar Zebari said on Thursday that Baghdad wanted U.S.-led forces to stay when he addressed the U.N. Security Council on a U.S.-British draft resolution on the planned U.S. handover on June 30.

"I stress that any premature departure of international troops would lead to chaos and the real possibility of a civil war in Iraq," Zebari said.

The question of who has the final say over action by U.S.-led forces after June 30 has become a burning issue for all parties involved in the Security Council debate.

France, Russia, China and other council members have forced the United States and Britain to come up with a second draft of the resolution and say they are still not happy with it.

Zebari said Iraq did not want veto power over actions by U.S. troops but said "we should have a say in endorsing this kind of (major) operation."

He also opposed the desire of France, Russia and China to have a fixed date for the U.S.-led force to withdraw, saying this would help those who fostered chaos. Instead he said an Iraqi government should have the right to ask them to leave.

Washington made clear again the sovereignty it is offering on June 30 will be subject to 138,000 American soldiers having the last word on any military action they deem essential.

"There could be a situation where we have to act and there may be a disagreement and we have to act to protect ourselves or to accomplish a mission," Secretary of State Colin Powell said in an interview with Middle East Broadcasting.

BLAIR CONFIDENT

British Prime Minister Tony Blair, President Bush's closest ally on Iraq, said he believed any differences could be overcome and that a resolution would be passed soon.

"I am reasonably optimistic that it will be done in a pretty short space of time," Blair told reporters in London.

U.S. and British officials would like a vote next week, but delays are possible.

In Iraq, a rebel cleric agreed to new steps on Friday for his militia to stop fighting, and the top Shi'ite cleric Ayatollah Ali al-Sistani issued a vote of confidence in the new interim government.

The developments were fillips for Washington and the interim government, despite the wrangling at the Security Council.

Shi'ite politicians said after hours of talks that rebel cleric Moqtada al-Sadr had agreed to fresh measures to shore up a shaky truce and end weeks of fighting in Iraq's holy Shi'ite cities with U.S.-led forces.

They said Sadr had agreed to withdraw his Mehdi Army fighters from the southern city of Najaf within two days as long as U.S. forces also withdrew, and had proposed neutral monitors.

Sadr announced last week he would withdraw his militiamen from Najaf and the nearby town of Kufa, and in return the U.S. military said it would suspend offensive operations.

But the truce has failed to take hold and there have been frequent skirmishes.

On Thursday, gunfire and explosions erupted in Najaf, some 100 miles south of Baghdad. Shopkeepers hurriedly closed up and women and children fled from the area.

FIGHTING AT CEMETERY

Witnesses said the fighting began when two U.S. tanks advanced toward Najaf's cemetery, where some militiamen were still dug in.

At least five Iraqis were killed in clashes in Kufa, hospital sources said.

Iraq's top Shi'ite religious leaders have been highly critical of Sadr for fighting in holy cities, but have also said the U.S. military response was heavy handed.

Sistani, who holds great sway over many of Iraq's Shi'ite majority, said the interim government lacked "electoral legitimacy" but was a step in the right direction and would succeed if specific goals were met.

"The hope is that this government will prove its worthiness and integrity and its firm readiness to perform the mammoth tasks it is burdened with," said Sistani, urging it to erase the marks of occupation and secure full sovereignty from the U.N.

Sistani, whose Shi'ite community was oppressed by Saddam Hussein's secular Sunni-dominated administration, scuppered an initial plan for handing power to Iraqis.

A U.N. resolution must hand Iraq sovereignty in all "political, economic, military and security" issues, he said.

Two U.S. Marines were sentenced to prison after pleading guilty to charges that they gave electric shocks in April to an Iraqi inmate who had thrown rubbish.