The United Nations Security Council voted overwhelmingly yesterday to impose a worldwide embargo on trade with Iraq and Kuwait, setting the stage for a multinational confrontation with Iraqi President Saddam Hussein and raising fresh concerns about the thousands of foreigners stranded in the war zone.

At the same time, Saddam called in the ranking U.S. diplomat in Baghdad and told him categorically that Kuwait now belongs to Iraq and there was no going back, according to administration officials. "It's a done deal," one U.S. official said, characterizing Saddam's message.

Another official said Saddam appended a specific warning that if Saudi Arabia shuts down the Iraqi crude oil pipelines that cross the Saudi desert to the Red Sea, Iraq will attack the kingdom. The warning further stated that if American forces intervene in the region, Iraq will "embarrass" the United States, the official said.

Iraq girded its capital city for war by preparing evacuation plans for the 4 million people of Baghdad and issuing automatic weapons to tens of thousands of citizens and supporters, according to members of the ruling Arab Baath Socialist Party.

In Kuwait, the occupation force kept a tight grip on the capital, maintaining a news blackout and shutdown of telephone and other international communications and keeping the international airport and seaports closed. One Middle East newsletter said Kuwait's oil-export facilities were shut down.

Enforcing the U.N. resolution could quickly escalate to military action, according to administration officials, and Saddam's bellicose warning to Washington highlighted the building tension in the Middle East on the fifth day of the crisis provoked by Iraq's invasion of Kuwait last Thursday.

Diplomatic action was centered at the United Nations, where the tough embargo resolution provided the international legal authority to effectively strangle Iraq's economy by cutting its pipelines and, if then necessary, blockade its ports and pipeline terminals in Jordan, Saudi Arabia and Turkey.

President Bush and British Prime Minister Margaret Thatcher appeared at the White House together after the U.N. vote and Bush said, "These sanctions must be enforced."

Thatcher added, "I cannot remember a time when we had the world so strongly together."

At the State Department, spokeswoman Margaret Tutwiler reiterated the four points of U.S. policy: the "immediate and unconditional withdrawal of all Iraqi forces from Kuwait"; the "restoration to power of a legitimate Kuwaiti government"; "ensuring the safety of all Americans in the area"; and "ensuring freedom of navigation" and "the free flow of oil from the region."

Quiet but urgent U.S. efforts were underway to persuade Turkish President Turgut Ozal and Saudi Arabian King Fahd to endorse the U.N. action and take the initiative to cut off Iraq's national income by shutting the pipelines.

"We need the Arabs {and Turks} to be out front," one official involved in the planning said. "We can't get in front of them. They need to be at risk in front of any forces in the area because we are going to play ball and it's time to choose sides."

One military official said that the worldwide assembly of U.S. forces and elements from the navies of Britain, France and the Soviet Union was like "a freight train going 100 miles per hour."

This official said there was significant concern at high levels of the military that the growing confrontation with Saddam was not leaving him a face-saving "out" from the crisis.

Defense Secretary Richard B. Cheney led a large delegation of senior U.S. officials to Jiddah, Saudi Arabia, to review options with King Fahd while Secretary of State James A. Baker III was set to depart Wednesday on a mission to win the Turkish president's commitment to enforce the U.N. embargo and to reassure him that his NATO allies will stand behind him.

Meanwhile yesterday, the United States and Egypt began quiet preparation to fly major elements of Egyptian airborne and armored forces to Saudi Arabia if they are needed to defend the Saudi regime from an invasion by about 100,000 Iraqi troops still in Kuwait.

Saudi Arabia sent tanks and some infantry forces north toward its border with Kuwait, where less than 25 miles away a major Iraqi armored force totaling tens of thousands of troops, hundreds of tanks and artillery pieces was encamped under blistering desert conditions.

U.S. aircraft carrier battle groups were soon to take up positions flanking the Arabian peninsula while major land-based U.S. air forces were being readied in Europe and the United States to deploy to bases in Saudi Arabia, military officials said.

U.S. intelligence monitoring showed four Iraqi divisions -- about 50,000 to 70,000 troops -- moving closer to the Kuwaiti border as the first small contingent of 80 Iraqi tanks was observed leaving Kuwait and returning to Iraq, military officials said.

In Jerusalem, a senior Israeli military source expressed skepticism that Western economic sanctions or military action would prove effective in forcing Iraq to retreat from its occupation of Kuwait, and he predicted that Saddam would attempt other conquests if he succeeded in consolidating control over the emirate.

The military source said that the Iraqi army, and particularly the divisions of its Republican Guard, have demonstrated the ability to fight well under difficult conditions and with long supply lines. However, to attack Israel an Iraqi force would have to cover hundreds of miles of open ground through Jordan, exposed to a preemptive attack by Israeli planes.

In the U.N. vote, Yemen, the only Arab state on the Security Council and a close ally of Iraq, abstained along with Cuba. Yemen's abstention reflected the division among the Arab states over whether to confront the victor of the Iran-Iraq war.

The U.N. resolution states that all member nations shall prevent "the import . . . of all commodities and products originating in Iraq or Kuwait" and also block "the export or transshipment" across their territory of Iraqi and Kuwaiti goods, including oil.

U.S. officials said the binding resolution would specifically require Turkey and Saudi Arabia to shut down the oil pipelines through their countries that carry virtually of Iraq's petroleum output to market.

Iraq yesterday drastically cut its crude oil shipments through the Turkish pipelines. The move was seen in Washington as a reminder to Turkey of its reliance on Iraq for half of its crude oil supplies. It also focused attention on Iraq's reliance on Saudi Arabia for its oil exports through Saudi pipelines, which carry 1.5 million barrels a day.

One analyst termed the Iraqi move as a "brilliant preemption" by Saddam to put greater pressure on Saudi Arabia, now the primary transshipper of Iraqi oil, either to allow the oil to continue flowing or to comply with the U.N. sanctions.

King Fahd appeared undecided yesterday, but one source who was following Arab diplomacy said Fahd has always "believed in a strong U.N. system." The source added, "In his thinking and ideology, he believes in strong U.N. participation and, I believe, at some point he will sign off.

{In Tokyo, stocks again fell Tuesday, picking up on Wall Street's sell-off over fears that sharply higher oil prices after the invasion will cause serious problems for the oil-dependent Japanese economy.

{The Nikkei stock average closed down 946.46 points at 27,653.07, Reuter reported. It was the third trading day of declines.}

Iraq remained defiant. Its army commander warned in Baghdad that "Iraq cannot be frightened."

Later in the day, the official Iraqi News Agency said that Saddam summoned James Wilson, the ranking American diplomat in Baghdad, and gave him a message for Bush "concerning U.S. behavior."

The news agency reported that Iraq and Saudi Arabia were tied by a non-aggression pact signed in early 1989 and that "Iraq respects its commitments." The report alleged that Washington was using the pretense of a threatened Iraqi attack on Saudi Arabia "as justification for interference in the region's affairs and to justify aggression on Iraq."

The report did not mention the specifics of the warnings issued by Saddam as reported by U.S. officials in Washington, but the dispatch carried a general warning "against any behavior that destabilizes the region . . . and brings security into danger."

One senior official, who would not discuss the details of the private meeting between Saddam and Wilson, said it did not represent "a very reassuring situation."

Saddam was unable to meet with U.S. Ambassador April Glaspie, one official said, because Bush had ordered her not to return to Baghdad from London, where she had been on vacation when the crisis erupted. "Why send a message? We don't have anything to say to him," the official said.

Also yesterday, a member of the Israeli parliament with ties to Iraq said that he believed Ala Hussein Ali, the head of the new Kuwaiti government appointed by Iraq, was a well-known Iraqi military figure.

Moshe Shahal, a Labor Party legislator, said in Jerusalem that a man named Ala Hussein Ali had been a general commanding Iraqi forces in the war against Iran and had published articles in the Iraqi press on military strategy and Iraq's strategic place in the Middle East. Shahal said that in one 1988 article, Hussein Ali depicted Israel as Iraq's major adversary in the Middle East and predicted that Israel would attempt a preventive strike against Iraq.