CLINTON THREATENS TO USE SANCTIONS TO FORCE OUT SERB.

Byline: Craig R. Whitney The New York Times

President Clinton threatened Serbia on Saturday with reimposition of United Nations economic sanctions if it did not use its influence to press Dr. Radovan Karadzic, the Bosnian Serb leader indicted on charges of war crimes, to step down from political office before the Sept. 14 elections in Bosnia.

Clinton, speaking at the end of a gathering of eight leaders of industrial democracies here, also announced that Gen. Wayne Downing, former commander in chief of the U.S. Special Operations Command, would lead an investigation into Tuesday's bombing that killed 19 U.S. military personnel in Dhahran, Saudi Arabia, and make recommendations within 45 days on how to prevent further attacks like it.

``We want Mr. Karadzic, in the words of the secretary of state, out of power and out of influence,'' Clinton said at a news conference. ``And we think that is very important.''

The president and his wife, Hillary Rodham Clinton, then flew to Paris late Saturday afternoon for dinner with President Jacques Chirac and his wife, Bernadette, before flying on to Florida for a memorial ceremony for the 19 Air Force personnel killed in the Dhahran bombing.

Saturday morning, the leaders attending the summit meeting once again warned Karadzic to resign his public functions as required by the Bosnia peace agreement negotiated last year in Dayton, Ohio.

They said they were ready to consider reimposing United Nations economic sanctions on any party to ensure compliance with the accords, thus vaguely threatening Serbia with economic punishment if it did not make good on repeated promises to get Karadzic out.

But the summit-meeting leaders, who included Russian Prime Minister Viktor Chernomyrdin on Saturday - President Boris Yeltsin did not come because of his campaign for re-election - did not endorse a call by Carl Bildt, the international coordinator in Bosnia, to give Karadzic until Monday to step aside, or else.

``It was not a matter for decision by the summit,'' Chirac said, though he added that he hoped Karadzic would step down. A German diplomat said the expectation was that Karadzic would step down as president of his self-styled Bosnian Serb republic this weekend.

President Clinton's press spokesman, Mike McCurry, said that Bildt had authority under the Dayton accords to recommend a reimposition of sanctions by the U.N. Security Council, and that the leaders at the meeting would support any recommendation he made.

They pledged to contribute ``substantially'' to preparations for the Sept. 14 elections in Bosnia by helping to bolster independent news media there and by sending 2,000 observers to ensure that the vote is free and fair. And they urged the NATO peacekeepers to increase their activities to provide the atmosphere of security the electoral process needs.