President Bush yesterday pressed for a complete international economic and arms embargo against Iraq, including the shutdown of Iraq's two oil export pipelines, and U.S. officials said a multi-nation naval blockade may be imposed to further isolate the government of President Saddam Hussein.

After a day of diplomatic overtures and internal White House meetings, Bush said the sanctions approved by the United Nations yesterday "must be enforced." Flanked by British Prime Minister Margaret Thatcher and NATO Secretary General Manfred Woerner, the president said he was "ruling out nothing at all" in U.S. efforts to force the invading Iraqi forces to withdraw from Kuwait.

Woerner, who discussed NATO's role in implementing the sanctions with Bush, said, "This is the moment for the West to show cohesion, determination, and to make it clear what cannot be accepted in this world."

Late yesterday, Bush called his top national security aides to the White House for a meeting that one senior official said focused on the energy implications in the United States should efforts to embargo Iraqi oil exports succeed. "The session dealt with the bad side of success," said one official, as well as efforts to persuade other nations to increase their oil production.

Earlier, the State Department announced that at least 28 Americans were among the foreigners who were removed by Iraqi troops Monday from their hotels in Kuwait and taken to Baghdad. "We hold Iraq responsible for their safety," said State Department spokesman Margaret Tutwiler.

In a multifaceted U.S. diplomatic effort to draw the line against Saddam, the White House announced that Bush was dispatching Secretary of State James A. Baker III to Turkey Wednesday to demonstrate U.S. support for Turkish moves to cut the oil flow from Iraq.

Said a senior official, "If you want the Turks to do something risky, we have to show them we're behind them." However, the Iraqis drastically reduced the oil pumped in their pipeline through Turkey, leaving the flow through the pipeline in Saudi Arabia untouched. The United States wants both pipelines closed, but officials would not say what commitments were received by either country if they agreed to do so.

Administration officials said the United States was not attempting to put in place a naval blockade to halt Iraq's oil from reaching export markets, but may turn to that later. Thatcher said yesterday "you would have to consider joint action such as a blockade" after other steps are taken.

Bush, asked about Turkey and Saudi Arabia cutting Iraq's pipelines, declined to go into what he called the "specific request" to those countries. But, he said, the U.N. resolution "gives an awful lot of muscle to countries and we want to see them use it." "I think you'll see a lot of countries now coming together to deny this man access to any market at all," Bush said of Saddam.

At the same time, Defense Secretary Richard B. Cheney yesterday reported to Bush from Saudi Arabia on what White House press secretary Marlin Fitzwater called the "threat by Iraqi forces to that country." Cheney carried intelligence information about the Iraqi troop buildup along the border with Saudi Arabia in an attempt to persuade the Saudis to allow the United States to use their country for basing and other needs in a gulf military operation. The discussions between Bush and Saudi King Fahd and Cheney and Saudi officials "involve appropriate ways to defend their country," Fitzwater said.

Meanwhile, White House and State Department officials yesterday continued their grim assessment of the situation in the gulf. Fitzwater said the situation "remains extremely serious. There is no information suggesting that Iraqi military units are departing Kuwait." Instead, he said, the presence of Iraqi troops in Kuwait remains "extremely large and threatening." Tutwiler said Iraq appears to be increasing the size of its forces along the border between Kuwait and Saudi Arabia.

Bush and Baker yesterday engaged in another round of diplomatic phone calls aimed at pushing for enforcement of the U.N. economic sanctions as the first solid international step in pressuring Iraq. In addition to his meetings with Thatcher and Woerner, Bush dined with Canadian Prime Minister Brian Mulroney and spoke with Italian Prime Minister Giulio Andreotti, who is serving as president of the European Community.

Mulroney said afterward that if the pipelines are shut down and shipping interdiction is successful in accord with the U.N. resolution, the Iraqis "would have a great deal of difficulty in selling their product . . . {and} in buying products that they need for their citizenry." Turkey deserves NATO protection if necessary if it shuts off Iraq's pipeline, he said.

Fitzwater said Jordan's King Hussein called Bush Sunday night, which came after the president made clear in a news conference his annoyance with Hussein and other Arab leaders who have not joined in the condemnation of Iraq.

The spokesman said the King had restated his position and Bush had restated his. The conversation, Fitzwater said, was "frank and cordial."

At the State Department, Tutwiler announced that Baker and Soviet Foreign Minister Eduard Shevardnadze spoke yesterday about U.S.-Soviet cooperation in enforcing the economic and arms embargo against Iraq. One official said Shevardnadze expressed the same irritation about Saddam that Bush had Sunday when the president said he had lied and laid down a firm line against Iraq.

The Soviets, who had been Iraq's largest arms supplier, were among those who had reassured the United States that Iraq had no intention of invading Kuwait.

State Department spokesman Margaret Tutwiler yesterday outlined four policy objectives the United States is pursuing to resolve the crisis involving Iraq's invasion of Kuwait:

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.

Ensuring freedom of navigation in the Persian Gulf, and the free flow of oil from the region, which has been the policy of the United States since 1949.