Washington ? The United States may have to alert thousands more National Guard and Reserve troops within weeks that they are needed for duty in Iraq, the Pentagon’s second-ranking general said Wednesday.

The Bush administration still hopes that Turkey, India, Pakistan or South Korea will contribute thousands of troops for security duty in Iraq, said Marine Corps Gen. Peter Pace, vice chairman of the Joint Chiefs of Staff.

But military planners are not counting on it.

“Hope is not a plan,” Pace said in an interview with a group of reporters at a Washington hotel.

Although reservists are called upon to serve in every overseas conflict, the scope of their involvement and length of their duty in Iraq have raised politically sensitive questions about whether the Bush administration is asking citizen soldiers to shoulder too much of the burden.

The United States has about 130,000 troops in Iraq, of which at least 20,000 are National Guard and Reserve.

Of the 302 U.S. troops who have died in Iraq since the war began, at least 47 were National Guard or Reserve.

An additional call-up is more likely if the administration falls short of its goal of persuading other countries to contribute a total of 10,000 to 15,000 troops for security duty in Iraq. The Pentagon needs to know soon whether it can count on them being there early in 2004.

Thus, decisions about activating reserves are coming soon — because waiting longer would cut into the mobilization and training time they would need to deploy early next year.

“We need to be making decisions about alerting reservists over the next four to six weeks,” Pace said.

President Bush did not receive any offers of troops for Iraq during two days of meetings with foreign leaders at the United Nations this week, said a senior U.S. official, who added that the question of sending troops did not even come up during Bush’s talks with the leaders of Pakistan and India.

The United States will continue seeking a new U.N. resolution designed to encourage other countries to send troops, but it may take months to work out, said the official, speaking on condition of anonymity.

Sen. Frank Lautenberg, D-N.J., said the prospect of additional reservists being called up for duty in Iraq reflects the administration’s failure to build an adequate international coalition.

“More American families now face possible separation because of the failed diplomacy of the Bush administration,” he said, “The president’s go-at-it alone policy has not encouraged foreign leaders to send their troops to Iraq to assist our men and women, who are stretched thin.”

Defense Secretary Donald H. Rumsfeld told a Senate committee Wednesday that U.S. allies are likely to commit only a limited number of forces, beyond a British-led international division that is operating in southern Iraq and a Polish-led division that recently replaced a U.S. Marine division.

“We’re not going to get a lot of international troops with or without a U.N. resolution,” Rumsfeld said. “I think somewhere between zero and 10,000 or 15,000 is probably the ballpark.”

Pace, in his comments, referred to possibly mobilizing National Guard and Reserve units beyond those already identified as part of the U.S. plan for rotating forces in Iraq.

“It’s not a given that the force would have to be Reserve or Guard,” he added. It could be an active-duty Army or Marine force, although they are stretched thin with worldwide commitments.

Among the factors to be weighed:

l Is the overall level of security within Iraq likely to be better, worse or about the same four to six months from now, when the Pentagon’s troop rotation plan calls for an as-yet-unidentified international force to take the place of the Army’s 101st Airborne Division?

l How many more Iraqis can be trained by then for security duties to replace American or international troops?

l How many foreign troops will be provided, beyond those already in place?

l If the foreign contributions fall short, how many active-duty U.S. troops would be available to send to Iraq?

Gen. John Abizaid, chief of U.S. Central Command, which is running the war in Iraq, told the Senate Appropriations Committee on Wednesday that about 170,000 National Guard and Reserve troops were on active duty. Of that total, about 120,000 are performing duties related to Iraq. Most of the rest are involved in other aspects of the war on terrorism, including duty in Afghanistan.

In the interview, Pace said that by late October or early November “we should be alerting those forces that may need to be called up” if it is not yet clear that other countries can be counted on to contribute to a third multinational division to relieve the 101st Airborne.

He said Abizaid would be making some decisions soon.

“We’re not there yet to be able to say with certainty that ‘X’ number of folks will be from active and ‘Y’ number should be from reserves,” he said.

Once those calculations are made they will be provided to Rumsfeld “so that he can make his decision … and then get the word out to the reserves if it’s going to be them: ‘We’re going to need you to get ready.”‘

Separately, the Pentagon’s personnel chief, David Chu, has approved a new policy that will allow U.S. troops — both active duty and Reserve — who are in Iraq on 12-month assignments to take 15 days of vacation in the United States at some point during their tours. They will be permitted to fly free of cost to Atlanta, Dallas, Los Angeles or Baltimore. Travel inside the United States beyond those cities would be at the service member’s own expense.