UNITED NATIONS -- The United States, France and Britain ran into strong opposition Wednesday from Russia and Algeria over their threat to impose sanctions against Syria if Damascus fails to cooperate fully with a UN investigation into the assassination of Lebanon's former Prime Minister Rafik Hariri.

Russia's opposition to sanctions against Syria could spell serious trouble for the draft resolution that the three countries circulated late Tuesday to pressure Damascus to cooperate because Russia has veto power in the UN Security Council.

The Security Council scheduled consultations late Wednesday on the draft resolution, which strongly backs a report by the UN investigating commission issued last week. The commission, led by Detlev Mehlis, implicated top Syrian and Lebanese security officials in Hariri's assassination and accused Syria of not cooperating fully with its probe.

President Vladimir Putin, in a telephone conversation Tuesday with Assad, welcomed Syria's stated willingness to cooperate with the investigation and emphasized that the council must proceed carefully.

The two discussed the "urgent need for cautious action by the international community in order to prevent the emergence of new sources of tension in the region," the Kremlin said in a statement.

Both Russia and China have expressed concern about any actions that might further destabilize the Middle East.

Pressure on Syria was likely to intensify following Wednesday's report by the UN special envoy on Syria-Lebanon, Terje Roed-Larsen, who said there had been no "tangible results" on disarming Lebanese militias, including Hezbollah.

He noted recent reports suggesting an increasing influx of weapons from Syria to Palestinian militia groups in Lebanese refugee camps, in violation of a council resolution adopted in September 2004 demanding that all militias be disarmed.

"The government of Syria has informed me that smuggling of arms and people across the Syrian-Lebanese border does indeed take place, albeit in both directions," he said.

Roed-Larsen said the inclusion of Hezbollah in the new Lebanese government indicated its possible transformation from an armed group to a political party, but he stressed that "operating as a political party and as a militia is contradictory ... [and] impossible to reconcile" in a democracy. He urged all parties to comply with the disarmament demand without delay.

Following the withdrawal of Syrian troops from Lebanon, Roed-Larsen said the country "is witnessing a momentous transition." He said his highest priority was to fully restore Lebanon's sovereignty and political independence and reiterated that the September 2004 resolution should be implemented "in a way that would best ensure the stability and unity of Lebanon, Syria and the wider region."

Mehlis' investigation has been extended until Dec. 15, and he urged Syria to help "fill in the gaps" about who orchestrated the terrorist attack in the coming weeks.

The resolution introduced Tuesday would require Syria to detain anyone the UN investigators consider a suspect in Hariri's killing and allow the individual to be questioned outside the country or without Syrian officials present. It would also immediately freeze the assets and impose a travel ban on anyone identified as a suspect by the commission.

U.S. Ambassador to the UN John Bolton said Wednesday that Syrian President Bashar Assad would not be exempt from being questioned.

"It absolutely includes the president of Syria," he told reporters. "No person is above the law, and the president's had time to talk to the media ... If he has time to do that, he has time to talk to commissioner Mehlis."

Bolton defended the draft resolution's intention to consider "further measures," including economic sanctions, if Syria refuses to cooperate, saying it was "part of sending a strong signal to Syria."

"As the Russian government has the chance to review the resolution, we're hoping that we're going to get their support for it," he said.

But Russia's Foreign Ministry spokesman Mikhail Kamynin, appeared quite adamant.

"Russia opposes sanctions against Syria," he said while accompanying Foreign Minister Sergei Lavrov on a trip to Israel, Russian news agencies reported. "Russia will be doing everything necessary to prevent attempts to impose sanctions against Syria."

Algeria's UN Ambassador Abdallah Baali, whose country is the only Arab member of the Security Council, said the draft "definitely raises difficult problems for Algeria, probably other countries."

"Our wish is to see Syria cooperate with the commission," he said. "The draft resolution should focus on assisting the commission in finding the truth, the whole truth and nothing else. ... In general, we don't like sanctions."

The draft resolution would have a mandate under Chapter VII of the UN Charter that is militarily enforceable. Several countries, including the Philippines, have said they would prefer a Chapter VI mandate that would not authorize military force.

The Mehlis report caused an uproar in the region and brought swift denials from the Syrian government, which called the report biased, politicized and an American plot to take over the region.