WASHINGTON — One of the national finance chairmen for Senator Clinton presidential campaign left Damascus last night after a visit there as part of a RAND Corp. delegation to meet with Middle Eastern leaders.

According to the Syrian press, the RAND delegation met with President Assad on Wednesday, the day the world learned that a Hezbollah master terrorist, Imad Mugniyeh, was slain in a car bombing in the Syrian capital.

The New York Sun confirmed the presence of the Clinton campaign official, Hassan Nemazee, on the RAND delegation through two sources familiar with the trip. In addition, the night manager of the Four Seasons Hotel in Damascus told the Sun: “Mr. Hassan Nemazee has been checked out of the hotel. He left the night of the 14th.”

The Clinton campaign offered no comment last night. Mr. Nemazee’s assistant in New York would only say Mr. Nemazee was traveling.

The Sun reported Tuesday that the RAND delegation trip to Syria was headed by Zbigniew Brzezinski, a foreign policy adviser to Mrs. Clinton’s rival for the Democratic presidential nomination, Senator Obama. Mr. Brzezinski was the national security adviser to President Carter.

On Wednesday, Mr. Brzezinski issued a statement to the Syrian press that said the talks with Mr. Assad “dealt with recent regional developments, affirming that both sides have a common desire to achieve stability in the region, which would benefit both its people and the United States.”

Mr. Brzezinski endorsed Mr. Obama in August and has advocated for America to engage Syria and Iran as part of a grand bargain to stabilize Iraq. This was a key recommendation of the bipartisan Iraq Study Group and has been a Democratic default position on the war since last January. In March, the speaker of the House, Rep. Nancy Pelosi, a Democrat of California, paid a visit to Mr. Assad in a tour of the Middle East.

Mrs. Clinton, who at times has advertised herself as more hawkish on foreign affairs than her rival for her party’s nomination, has taken a different stand on the issue. Mrs. Clinton called Mr. Obama “naïve” when he said last summer he would meet with foreign adversaries.

But the presence of Mr. Nemazee, a former fund-raiser for Senator Kerry’s presidential campaign in 2004 and a close ally of the Clintons, raises questions for some analysts about what Mrs. Clinton would do as president with regard to Syria, a nation General Petraeus until recently has said was facilitating the travel of Al Qaeda terrorists into Iraq and the United Nations is investigating for its role in the assassination of Lebanon’s president, Rafik Hariri. The three-year anniversary of his murder was yesterday, bringing supporters of the slain leader to the streets of Beirut.

Mrs. Clinton’s Senate office issued a statement marking the anniversary. It said, “The United States and the international community have a strong interest and a moral responsibility to hold Syria and Iran accountable for their defiance of United Nation resolutions 1559, 1680 and 1701. And the Special Tribunal for Lebanon created by resolution 1757 should be established as soon as possible and its independence maintained.”

A research fellow at the Foundation for Defense of Democracies, Tony Badran, praised that statement, but said the presence of Mr. Nemazee in the RAND delegation to Syria raised questions about Mrs. Clinton’s support for Lebanon’s democracy movement.

“Given that the visit coincided with that anniversary and the discovery that Syria was harboring one of the most wanted terrorists on the planet, this visit by a top finance chair raises certain questions about the policy she intends to pursue with Syria if she should become president,” Mr. Badran said.

In 1999 Mr. Nemazee was nominated by President Clinton to serve as ambassador to Argentina but the nomination was eventually withdrawn. He is also one of the founders of the Iranian American Political Action Committee. Mr. Nemazee has said he disagreed with Senator Kerry’s call for negotiating with the Iranians and favored instead a democratic regime change there.

A biography of Mr. Nemazee at the Iranian American Political Action Committee Web site lists him as a 1972 graduate of Harvard College who was born in 1950.