WASHINGTON – The White House is poised to nominate its current ambassador to Afghanistan to head its embassy in Baghdad.

Zalmay Khalilzad, who before the war in Iraq was America’s envoy to the Iraqi opposition, is the consensus choice to succeed John Negroponte, who was named last month as America’s first director of national intelligence, The New York Sun has been told.

“He is pretty much a lock,” a senior administration official told the Sun yesterday. “Zal’s name has been in the pipeline for the job for some time and there have been no major objections.” That Mr. Khalilzad was the choice to be the next ambassador to Baghdad was also confirmed by officials at the State Department and the Pentagon.

The American Embassy in Iraq is one of America’s largest and most important diplomatic posts. Not only does the ambassador manage the largest single country aid program, but the ambassador will play a vital role in smoothing out differences between factions in the government whose formation is now being negotiated by Iraqi leaders.

As ambassador to Afghanistan, Mr. Khalilzad has been one of America’s few direct diplomatic channels to the Islamic Republic of Iran. In the spring of 2003, he led talks in Geneva with the Islamic republic over a proposed swap of senior leaders of Al Qaeda in exchange for members of the Mujahedin e-Khalq, an anti-Iranian militia currently in the custody of American soldiers in Iraq. The deal was ultimately vetoed by the White House. Earlier, Mr. Khalilzad included Iranian envoys in 2001 and 2002 in international meetings to help rebuild Afghanistan.

Earlier this month, Mr. Khalilzad held meetings with Kurdish leaders in northern Iraq to discuss the prospects for the new government and to pass a message to the Iranians urging them to remain helpful during the political transition. Ibrahim al-Jafari, the candidate for prime minister from the United Iraqi Alliance, the slate of largely Shiite parties that won the most seats in the January 30 elections, was widely considered to be backed by Tehran during the backroom dealings before his name was announced last month.

As the ambassador to Afghanistan, Mr. Khalilzad has encouraged negotiations between Hamid Karzai’s government and the remnants of the Taliban. He has also urged the new government in Kabul to incorporate warlords in the Cabinet, recently praising the decision to make Abd al-Rashid Dostum the chief of the country’s army. In Iraq, he will probably be faced with similar choices regarding the vanquished Baath Party. While the Coalition Provisional Authority made it illegal for senior Baathist officials to participate in the government, that decision was reversed by the interim prime minister, Ayad Allawi. Leaders of the slate that won the majority of seats in Iraq’s transitional assembly have repeatedly said they intend to purge former Baathists from the security services and military.

Mr. Khalilzad was asked Tuesday at the American Enterprise Institute what parallels he saw between Afghanistan and Iraq, and he said that in both cases it was important to erect a truly representative government. “In a general way, I can say that the establishment of a legitimate political order, and creating the belief that … one is committed to a process that will create a legitimate political order that is representative, is important,” he said. He added that economic reconstruction and establishing security were important, too. He added that in Afghanistan it was important for “the use of force to be minimal, but if necessary, has to be overwhelming.”

A spokesman for the Iraqi National Congress’s leader, Ahmad Chalabi, said yesterday he would welcome the nomination of Mr. Khalilzad, a man he remembered fondly when he was the ambassador-at-large for free Iraqis. “He is committed to freedom and democracy,” the spokesman, Entifadh Qanbar, said. “His service has been for the liberation and democracy in Iraq when he worked with the opposition. He was one of the first brave officials who came to Baghdad who talked directly to Iraqis in an encouraging way about democracy and freedom.”

A former chairman of the Defense Policy Advisory Board, Richard Perle, was also pleased by the news. “He’s very capable. He has done an excellent job in Afghanistan. He has White House experience which will be invaluable in his service as ambassador in Baghdad,” he said yesterday.

Before serving as White House envoy to the Iraqi opposition, Mr. Khalilzad was senior director for Southwest Asia, Near East, and North African affairs at the National Security Council. After President Bush won the election in 2000, he was director of transition for the Pentagon.