The Egyptian President Hosni Mubarak has led international condemnation of Israel's missile attack on what it claimed was a Syrian-based Palestinian terrorist camp.
The German Chancellor Gerhard Schroeder, currently visiting Egypt, said it complicated regional peace efforts.
Jordan argued the action could spread violence across the region.
Damascus itself said Israel had targeted a civilian site and marked a "grave escalation" of tensions in the Middle East. It urged the United Nations Security Council to meet immediately.
The Israeli army said it had attacked a base near Damascus used by militant groups including Islamic Jihad, which claimed responsibility for a suicide bombing that killed 19 people in a restaurant in the northern port city of Haifa on Saturday.
Several other Arab countries condemned the raid, the firstdeep inside Syria since the 1973 Middle East war, but there wasno immediate comment from Washington - the main power broker inthe region and driving force behind a battered "roadmap" peaceplan to end three years of Israeli-Palestinian violence.
"We condemn what happened today concerning the aggressionagainst a brotherly state under the pretext that someorganisations exist there," Mubarak said in a joint newsconference in Cairo with Gerhard Schroeder.
Schroeder said regional peace efforts "become morecomplicated when...the sovereignty of a country is violated.This is why the action in Syria is not acceptable".
In Jordan - along with Egypt the only other Arab state tohave signed a peace treaty with Israel - the foreign ministertempered condemnation of Israel with apparent criticism ofPalestinian suicide bombings.
"An attack on a brotherly Arab country...would push theentire region into a continuous cycle of violence," ForeignMinister Marwan al-Muasher told state-owned television.
"The time has come to review these Israeli operations...andthe time has come to review the acts that are also done by someorganisations including yesterday's act," Muasher said, in anapparent reference to Saturday's bombing in Haifa.
Pro-Western Jordan has important political and economic tieswith the United States, Israel's closest ally, but the public ispro-Palestinian.
Qatar said Israel's action would increase regional tensions."Such actions are a dangerous threat to peace in the MiddleEast and take the region back into an atmosphere of war,violence and tension," a Foreign Ministry official told thestate news agency QNA.
Britain, a key US ally, said Israel was entitled to defenditself, though it also called for restraint.
"Israel is of course entitled to take steps to protectitself from terrorist attack, but these steps should be withininternational law," a British Foreign Office spokesman told journalists:
The spokesman declined to say whether the British governmentconsidered Sunday's strike to be within international law.
"We have already urged and will continue to urge all sidesto exercise restraint," he said.
In Washington, both the White House and the State Departmentsaid they had no immediate comment on Israel's action.
President George W. Bush, did not answer a reporter'squestion on the strike as he was leaving a church service.