NEWS ANALYSIS : Ultimatum Cuts Both Ways for U.S. : Strategy: Move would increase the pressure on Hussein. But it would reduce American maneuverability.

The Bush Administration, by calling on the United Nations to send an ultimatum to Iraq, increases the pressure on Saddam Hussein but also reduces U.S. ability to maneuver in the increasingly complex Persian Gulf crisis.

The U.N. Security Council plans to vote Thursday on a resolution setting a deadline for Iraq to withdraw from Kuwait and authorizing the use of military force if the Baghdad regime refuses to comply.

The five permanent council members have approved a January deadline, with the exact date open to negotiation.

According to informed sources in both the United States and Saudi Arabia, the Administration had hoped to avoid setting a specific date, preferring instead an open-ended mandate that would permit the international armed forces in the gulf to go on the offensive at a time of their own choosing.

Earlier reports had indicated that the United States favored a deadline, but sources said it was the Soviet Union that insisted on fixing a date, apparently to give diplomats one last chance to persuade Hussein to withdraw peacefully.

From the U.S. standpoint, the ultimatum may get Hussein’s attention in a way that 10 previous U.N. resolutions have failed to do.

However, the strategy also gives Iraq assurances that it will not be attacked until the deadline is reached, robs the anti-Iraq coalition of strategic surprise and increases the pressure on Washington and its allies to take action shortly after the deadline passes.

For weeks, Secretary of State James A. Baker III tried to discourage talk about a specific deadline because he was convinced that it would limit American flexibility. However, according to a well-informed Saudi official, the United States agreed to include a deadline to win Soviet support. As a practical matter, the resolution would have little chance of success without Moscow’s backing.

Putting the best possible face on the inevitable, White House Press Secretary Marlin Fitzwater said that a deadline “lets Saddam Hussein know exactly what kind of time frame we’re talking about. It lets everyone know exactly how strong our intentions are. It takes some of the uncertainty out of the situation.”

Critics of the strategy say that is precisely what is wrong with it.

“It’s a terrible idea,” said Judith Kipper, a guest scholar at the Brookings Institution in Washington. “This is a person (Hussein) who is paranoid. He is not familiar with the ways of the world. There is a date and he will take that as a declaration of war. Any date puts his back up against the wall.”

William B. Quandt, a former National Security Council Middle East expert, said that by setting a firm deadline, the Administration virtually rules out the option of giving economic sanctions time to work.

Although there is growing evidence that the trade embargo and other U.N.-imposed sanctions are beginning to have an impact on the Iraqi economy, no one thinks that economic pain alone will force Hussein to change course before the expiration of even the most lenient ultimatum now under consideration. If anything, a deadline would ease the economic pressure because it would signal Hussein that his foes have given up hope that the embargo will succeed.

Meanwhile, a Saudi official said that his government and the United States had hoped to avoid a specific deadline because they believe that Hussein would take more seriously an open-ended authorization for the use of force. The official said that both U.S. and Saudi officials believe that Hussein doubts the United States is ready to wage war.

The official said that the two governments had hoped to obtain passage of the U.N. resolution before President Bush’s trip last week to the Middle East.

Administration officials maintain that a U.N. resolution is needed to demonstrate that the United States and its allies are serious.

But Quandt said it will take more than a U.N. resolution to make credible the threat of force.

“I really do believe it will take something like an ultimatum with a deadline to persuade Saddam to back down,” he said. “But I don’t think the President can go down that road with just an international resolution as his basis for support. He also needs domestic support, and I’m not sure he’s got that now.

“The sharp drop-off in domestic support came with the second (troop) deployment and the way it was done, without adequate consultation with Congress and without a clear explanation of why it was done,” Quandt said. “That was a policy blunder. The President had handled the earlier phase quite well. It is reckless to take the country into what could be a costly war without strong public support at home.”

Times staff writer Douglas Jehl in Saudi Arabia contributed to this report.