Six key pro-Western Gulf Arab states have called on the United States to stop threatening Syria in the wake of the war in Iraq.
Ties between the US and Syria have long been strained
The Gulf Co-operation Council (GCC) - whose members control nearly half the world's known oil reserves - also said that setting up a transitional government in US-occupied Iraq was an urgent priority.
US officials have accused Syria of harbouring members of the former Iraqi regime and developing weapons of mass destruction - allegations that Damascus denies.
Economic and diplomatic sanctions have been threatened, and some US Government spokesmen have refused to rule out military action.
Tuesday saw US Defence Secretary Donald Rumsfeld confirm that a pipeline supplying Iraqi oil to Syria, apparently in contravention of United Nations sanctions, had been "shut off".
Later, US officials said a former leading member of the Iraqi intelligence service, Farouk Hijazi, was believed to be in Syria.
Correspondents say Mr Hijazi was a director of the Iraqi intelligence agency in the 1990s when it is alleged to have carried out a failed attempt to assassinate the then US President George Bush - father of the current president.
In other developments:
- US Central Command says its special forces in the Iraqi capital Baghdad have captured Abu Abbas, leader of Palestinian hijackers who seized an Italian cruise ship in the Mediterranean in 1985
- The UN could be sidelined for a second time over Iraq unless Security Council members co-operate on the country's post-war future, British Foreign Secretary Jack Straw warns
- US forces deny responsibility for the deaths of up to 15 people in a shooting incident in the northern Iraqi city of Mosul
- Amnesty International accuses the US and UK of putting more effort into securing Iraq's oilfields than into protecting its hospitals, water supplies and people
- Returning exiles and local leaders attend the first US-sponsored meeting aimed at setting up a new Iraqi administration.
Speaking for the Gulf Co-operation Council, Qatari Foreign Minister Sheikh Hamad bin Jassim al-Thani urged the US to moderate its tone against Syria.
United Arab Emirates
"We think the threat to Syria should stop. We reject any infringement of Syria's security," he said.
He added that the council "now considers Iraq occupied and we hope there will be a civil administration of the Iraqi people as soon as possible".
"The creation of an Iraqi transitional government is very important because the Iraqi people won't accept a government from outside for very long," he said.
'No war plan'
US Secretary of State Colin Powell has insisted that Washington has no intention of attacking any other countries in the Middle East.
"There is no war plan right now to go attack someone else," he said.
But he added that the US was expecting to see change in Syria.
"We hope that Syria understands now that there is a new environment in the region with the end of the regime of Saddam Hussein, and that Syria will reconsider its policies of past years," he said.
Rumsfeld has accused the Syrians of supplying the Iraqi military
Ties between the US and Syria have long been strained by US support for Israel and Syria's backing of the Lebanese group Hezbollah and radical Palestinian groups, which Washington considers terrorist organisations.
A statement released by the Syrian Government on Tuesday condemned US "threats and falsifications", saying that the "escalated language of threats and accusations by some American officials against Syria" was aimed at "damaging its steadfastness".
"The cabinet rejected these accusations and allegations and saw them as a response to Israeli stimulus and a service to its [Israel's] goals and expansive greed," the statement added.
And in an apparent response to the US accusations, Syria is preparing to introduce a resolution at the UN Security Council on Wednesday, calling for the Middle East to be declared a "zone free of weapons of mass destruction" - a clear reference to Israel's nuclear weapons programme.
The Arab League ambassador to the UN, Yahya Mahmassani, said US allegations against Syria were "unacceptable and unfounded".
"The Arab world is already engulfed with anger and frustration," he said.
Both the UK and Spain, crucial US allies in the war in Iraq, have declined to support the US over Syria.
UN Secretary General Kofi Annan has expressed concern that recent statements about Syria may further destabilise the Middle East.