U.S. Backs Off on Size of Bosnia Force : Balkans: Envoy indicates offer to send up to 25,000 troops to help police any settlement has been shelved. Serbs are warned to accept peace plan or face air strikes.

The Clinton Administration on Sunday backed away from a 2-year-old plan under which the United States would have sent as many as 25,000 U.S. troops to Bosnia-Herzegovina to help enforce any peace settlement there.

At the same time, a senior Administration official renewed the threat of North Atlantic Treaty Organization air strikes against Bosnian Serb positions if rebel leaders continue to reject the Administration’s diplomatic initiative to settle the Bosnian conflict.

Assistant Secretary of State Richard Holbrooke acknowledged that a smaller number of U.S. troops still might be sent to Bosnia as part of a NATO force if the combatants accept a peace settlement.

Holbrooke said a 1993 plan, under which an estimated 15,000 to 25,000 Americans would have been sent as part of a NATO force to police a settlement, has been quietly discarded. Under that plan, about 50,000 NATO troops, including the U.S. soldiers and Marines, would have swept into the Bosnian capital, Sarajevo, and other key cities.

“There was a general operations plan . . . which did involve numbers of that sort and higher,” he said. “That plan is not currently under discussion. A basic new planning exercise is under way within NATO . . . and those earlier numbers should not be regarded in any way as binding or definitive.”

Holbrooke, in an interview on NBC-TV’s “Meet the Press,” did not say how many U.S. troops the Administration would now send to enforce any peace settlement, but he stressed that, as with the earlier plan, the U.S. forces would be under NATO command.

The number of Americans “is the subject of an ongoing and intense dialogue being conducted by the United States military and our NATO allies at this very moment,” he said.

Holbrooke leads the reconstituted U.S. team trying to negotiate an end to the war in Bosnia. Eight days after the accidental deaths of three U.S. negotiators in Bosnia devastated the team and delayed the peace effort, Holbrooke said Sunday that he will visit Belgrade, the Serbian capital, this week for what he called “potentially decisive” talks with President Slobodan Milosevic, who long sponsored the Bosnian Serb rebellion.

So far, the Bosnian Serbs have shown no inclination to accept the U.S. peace plan. And Milosevic has maintained that he cannot force the rebels to agree to a settlement.

Under the current proposal, parts of which are still being kept secret, a federation of Bosnian Croats and Muslims would gain control over 51% of Bosnian territory while Bosnian Serbs would control 49%.

The main obstacle to such a settlement is the Bosnian Serbs, who now control about 70% of Bosnian territory and have refused to accept an accord in which they would have to give up a significant amount of land.

“We’re not going to make a major concession to get them to the table,” Holbrooke said. “They are the major obstacle to peace, and Belgrade will have to make some very tough decisions in the week to come.”

Holbrooke suggested that, if the Bosnian Serbs remain recalcitrant, they will soon face NATO air strikes.

“If this peace initiative does not get moving, dramatically moving, in the next week or two, the consequences will be very adverse to the Serbian goals,” Holbrooke said. “One way or another, NATO will be heavily involved, and the Serbs don’t want that. NATO will either assist the U.N. withdrawal or there will be more active NATO air over the skies. . . .”

“I don’t want to leave the impression that NATO air strikes start automatically if we don’t make a breakthrough in the next few days,” he cautioned. “I’m not going to give a tight time limit.”

Before meeting with Milosevic, Holbrooke is scheduled to stop in Paris to talk with Bosnian President Alija Izetbegovic and attend a meeting of the Contact Group of five nations--the United States, Britain, France, Germany and Russia--overseeing Bosnian peace efforts.