U.S. Ambassador John Bolton (search) used his new platform at the United Nations Thursday to issue a stern warning to two nations that President Bush has accused of destabilizing the Mideast and supporting terrorism.

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And if Bolton's recess appointment Monday by Bush was supposed to make him a leper at the United Nations, the way Bolton opponents predicted, no sign of it was evident during his debut at the U.N. Security Council Thursday.

Several ambassadors, including those from Algeria, Argentina, France, Russia and China expressed welcoming wishes and expressions of enthusiasm to working with the former State Department undersecretary.

Equally welcoming was the unanimity with which the U.N. Security Council (search) adopted a resolution denouncing recent terrorist violence in Iraq and calling on all 191 member nations to check the flow of weapons and money to insurgents there.

For his part, Bolton responded with kind words for the institution of which he has in the past been harshly critical.

"The constructive dialogue through which this text was developed demonstrates further the strength and resolve of the United Nations (search) to work together for a democratic, secure and prosperous Iraq," he said.

In both his prepared remarks and later, in an impromptu session with reporters at which the new ambassador refused to answer questions about anything besides the resolution, Bolton singled out two countries for playing a less than constructive role in Iraq's march toward democracy.

"We call on all members to meet their obligations to stop the flow of terrorist financing and weapons, and particularly on Iran and Syria," he said.

Along Iraq's porous northwest border, Syria contends it has already put more than 300 watchtowers and some 10,000 patrol troops, assets Damascus claims it has used to intercept "thousands" of would-be terrorists.

In a pointed rebuke after Thursday's formal session, Syria's U.N. ambassador faulted the United States and Great Britain for not supplying the Syrians with night-vision goggles as requested. Syrian Ambassador Fayssal Mekdad challenged Washington and London to match his country's effort.

"We would like to ask them: What have they done on the other side of the border? They have done nothing while Syria has taken all measures and done everything possible," Mekdad said.

After a meeting with Bolton, the Chinese ambassador to the United Nations told reporters that Beijing is coordinating efforts on keeping the Security Council at its present size. Aides to Bolton say the United States still supports the eventual addition of Japan to the list of permanent members.