The message came in the form of an "oral message" from US Secretary of State Colin Powell to Syrian President Bashar al-Assad that was delivered to Syrian Foreign Minister Faruq al-Shara by US ambassador to Syria Margaret Scobey on Thursday, the State Department said.

The message "was focused on the fact that Syria has a huge stake in the emergence of a unified and stable Iraq," spokesman Richard Boucher told reporters.

"It urged Syria to work closely with the rest of the international community to promote a stable Iraq," he said. "It also made clear to Syria that it needs to control the transit of its border by terrorists and people supporting the insurgents in Iraq.

"We feel that Syria had taken some steps, but that there is more that they can and should do in that regard," Boucher said.

Syria's official Sana news agency reported Thursday that Powell had asked Assad for help in bringing peace to Iraq where violence has spiralled in recent weeks amid US accusations that insurgents using Syria as an entry point to the country.

According to Sana, Powell asked Syria to do everything in its power to assist with the "pacification of the situation in Iraq" while preserving its unity.

That report came shortly after General Richard Myers, the chairman of the US Joint Chiefs of Staff, said in Baghdad that foreign fighters were still infiltrating Iraq from Syria and Iran, calling the situation unacceptable.