U.S. Ambassador John Negroponte (search) urged all countries Friday to contribute troops to a new force to protect U.N. staff in Iraq, a key element in Washington's campaign for a major U.N. presence after the United States relinquishes power on June 30.

Negroponte — widely believed to be President Bush's choice to replace L. Paul Bremer (search) as the top American envoy in Iraq after the hand over — said he envisions the world body playing a key role in the political transition and organizing elections by Jan. 31.

But Secretary-General Kofi Annan (search) on Tuesday ruled out sending a large U.N. team to Iraq "for the foreseeable future" because of increased violence and kidnappings. At least one country approached by the United States to contribute troops said it was too early to decide.

"The U.N. first has to decide to go before we consider it," said Pakistan's U.N. Ambassador Munir Akram.

Briefing the U.N. Security Council on the current situation in Iraq, Negroponte said the United States is committed to "stay the course" and ensure that Iraq becomes a peaceful democracy, despite the worst violence since Saddam Hussein was ousted last year.

He blamed insurgents including former supporters of Saddam Hussein (search), terrorists who have infiltrated Iraqs, and militias affiliated with radical elements for the wave of deadly ambushes and attacks — and he repeated Bush's pledge to get rid of armed militias and "to deal firmly with those who refuse to negotiate."

Despite the violence, Negroponte made clear that the United States wants the world body back in Iraq and is seeking help to ensure security for U.N. staff and facilities.

He said U.N. troops would be under the overall command of the U.S.-led multinational force authorized by the Security Council on Oct. 16, but stressed that it would be a "discreet, separate" entity. He indicated its operation would be like that of the NATO-led force in Afghanistan, which is under the overall command of U.S. troops hunting for remnants of Al Qaeda and the Taliban.

"It will be under unified command, under the coalition, but the force will be distinct enough that it will be exclusively dedicated to the protection of United Nations personnel," Negroponte said.

Security has been a major concern for the United Nations since two bombings at U.N. headquarters in Baghdad. The first, on Aug. 19, killed 22 people including top U.N. envoy Sergio Vieira de Mello. Two months later, following a spate of attacks, Annan ordered all U.N. international staff to leave Iraq.

At the request of the U.S.-led coalition and the Iraqi Governing Council, Annan sent his top adviser, Lakhdar Brahimi, to help the Iraqis decide on a broadly acceptable government to take power June 30, along with the U.N.'s top election expert, Carina Perelli, to help prepare for the January vote.

Negroponte told council members that the United States welcomes the "highly constructive recommendations" made this week by Brahimi for a caretaker government "and looks forward to hearing about them in greater detail."

Negroponte said he expects the role of a "broad-based U.N. mission" to be defined in a new U.N. resolution. He said he doesn't expect a draft to be presented to the Security Council "in the very near future but I'm sure that over the next several weeks this is an issue we're going to have to address."

During closed-door consultations after his briefing, diplomats said Britain's U.N. Ambassador Emyr Jones Parry sketched out five issues that London and Washington believe a new resolution should address: the end of the occupation; future political arrangements; the enhanced U.N role in Iraq; the continued military presence; and legal issues arising from the transfer of power.