A day after a massive bomb explosion killed the former Lebanese prime minister, the Security Council unanimously approved a statement condemning it as a terrorist act.

The 15-member Council requested an urgent report on the assassination, and called on all parties to implement a resolution passed last year, resolution 1559, demanding that Syria withdraw its troops from Lebanon.

Emerging from the Council meeting, Deputy U.S. ambassador Anne Patterson said the intent of the statement was to send a strong message.

"We don't know who did this horrible act at this point, but let me be clear that the message of the council is that other countries should get out of Lebanese affairs," she said.

Ambassador Patterson did not mention Syria by name, but she bristled when asked if the United States was trying to use Mr. Hariri's assassination to politicize the resolution demanding the withdrawal of foreign troops from Lebanon.

"Good grief, a man just got blown up in downtown Beirut in the middle of the day, and hundreds of people are injured," she said. "This is not a political act on our part. What you need to take on board here [understand] is that the Security Council has a long history of engagement on this issue and the message has been consistent: that other countries need to stop interfering in Lebanon. And this is only the most recent and most horrific demonstration of the effects of that foreign interference."

The Security Council statement stopped short of calling for an international investigation into Mr. Hariri's death, and Secretary-General Annan said he did not know who should do it. But the French U.N. ambassador, Jean-Marc de La Sabliere, said the intent was to shine the light of international attention on what he called "this horrible act."

"We are looking for two things, we want to know exactly the truth on what has happened in Lebanon yesterday, who is responsible for this terrible event," he said. "And we think that giving an international dimension to this quest for the truth is important."

Secretary-General Annan told reporters Tuesday his personal envoy on the matter of pushing for removal of Syrian troops in Lebanon had met with Syrian and Lebanese officials in the region last week. He would not divulge the content of his envoy's mission, other than to say he was pressing for Syria's compliance with the Security Council resolution.

Syria sent troops to neighboring Lebanon in 1976 to help quell a civil war, and an estimated 14,000 troops are still there. Damascus is widely seen as controlling Lebanese politics.

Resolution 1559, passed last September, called for the withdrawal of all foreign troops from Lebanon; a subsequent secretary-general's report said Syria had neither complied with the resolution nor given any timetable for doing so.