Alarmed U.S. Considers Stronger Action in Bosnia : Policy: President talks tough as Administration renews discussion of strikes against Serbian positions.

Clinton Administration officials, expressing alarm at the imminent fall of the Bosnian stronghold of Srebrenica, renewed talk Friday of air strikes against Serbian artillery emplacements and began a flurry of diplomatic consultations aimed at tightening sanctions against the Serbs and rallying international support for possible military strikes.

As Serbian-backed forces closed in on one of Bosnia-Herzegovina’s last Muslim enclaves, President Clinton, in some of his toughest talk since assuming office, said that “the time has come” for the United States and its European allies to reassess the effectiveness of the measures they have taken so far and to consider new steps to halt the advance of Serbian troops against Bosnia’s Muslim strongholds.

Clinton pointedly added that he “would not rule out any option” for dealing with the Serbs, except the introduction of American ground troops--a step he has consistently refused to take.

“We have to consider things that at least previously have been unacceptable,” Clinton said during a joint press conference with Japanese Prime Minister Kiichi Miyazawa. Clinton met with Miyazawa to discuss trade and U.S.-Japanese relations.

Meanwhile, at the Pentagon, a senior defense official said that air strikes are “on the table” if peace negotiations disintegrate. If allied nations approve, the official said, U.S. warplanes could target Serbian artillery positions around Sarajevo and other besieged Bosnian cities.

“There are no good options,” the senior defense official told reporters. “There are some that are less bad than others. The one that is less bad is probably the use of air strikes in some way against artillery.”

The volley of harsh rhetoric came after weeks of frustrating negotiations in which U.S. and allied officials have sought to head off the fall of Srebrenica and to blunt the Serbian forces’ relentless advances. One weary Clinton Administration official complained that in weeks of negotiations with U.S. and European envoys, “there has been no indication of good faith” on the Serbs’ part.

Clinton on Friday said he was “outraged” that the Serbs failed to sign a peace agreement negotiated by special U.N. envoy Cyrus R. Vance and European Community envoy Lord Owen. Owen himself on Friday abandoned months of diplomatic patience with the Serbia and called for military action to stop the Serbs, saying they might be persuaded to sign a peace accord if bombers were used to cut off their supply lines into Bosnia.

“I think we have an interest in standing up against the principle of ‘ethnic cleansing,’ ” Clinton said Friday. “If you look at the turmoil all through the Balkans, if you look at the other places where this could play itself out in other parts of the world, this is not just about Bosnia. On the other hand, there is reason to be humble when approaching anything dealing with the former Yugoslavia.”

Clinton Administration officials stressed that allied support is key to any further U.S. move and warned that no U.S. military strikes would be considered before the April 25 Russian referendum. Russian President Boris N. Yeltsin is seeking a vote of confidence from the people of his troubled republic and American officials acknowledged that a bold U.S. move against the Serbs, who have longstanding allies in Russia, could hurt Yeltsin politically.

But Administration officials said that they will not wait until after April 25, as they have promised in the past, to seek further U.N. sanctions designed to isolate the Serbs from the world community. A senior Administration official said that the United States instead would seek the new sanctions immediately and would press its allies to implement them without delay.

Secretary of State Warren Christopher said that if Srebrenica were to fall or be forced to surrender, then “all bets were off” as far as what the U.N. Security Council should do next and how soon it would act.

The British Foreign Office said that British Foreign Secretary Douglas Hurd and French Foreign Minister Alain Juppe had agreed to the accelerated pace.

Clinton Administration officials also said that Christopher conferred Friday with senior representatives of Yeltsin’s government to tell them of the U.S. decision to press quickly for the new sanctions. It was unclear, however, whether Russia would attempt to block the effort.

Late Friday, the U.N. Security Council, passing a resolution vehement in rhetoric but limp in enforcement, declared Srebenica a safe area that “should be free from any armed attack.” By a unanimous vote, the 15-member council demanded the withdrawal of all Bosnian Serb military units from the area.

But news of an impending Serbian victory on the ground seemed to allow almost no time to achieve the aim of the resolution.

The council’s ambassadors called on Secretary-General Boutros Boutros-Ghali to increase the numbers of U.N. peacekeepers in the area and to make an urgent report on the situation to the council.

The Security Council, however, did not authorize new powers to the defensive-minded peacekeepers, and its resolution did not detail how the Srebrenica “safe area” would be enforced.

But Ambassador Jamsheed Marker of Pakistan, president of the council this month, said the ambassadors would move quickly to tighten sanctions on Serbia should the Bosnian Serbs occupy the town.

The Administration’s new resolve was reflected by a key lawmaker, who on Friday broke ranks with the cautious mood on Capitol Hill and called for firm U.S. military action in Bosnia.

“The United States must lead the West in a decisive response to Serbian aggression, beginning with air attacks on Serb artillery everywhere in Bosnia and on Yugoslav National Army units in Serbia that have participated in this international crime,” said Sen. Joseph R. Biden Jr. (D-Del.), a leading member of the Senate Foreign Relations Committee.

“From talks with the most informed U.S. military officials, I am confident it would not require the introduction of a major Western ground force to deny the Serbs the victory toward which they are now headed in the face of Western apathy.”

Biden returned last weekend from a trip that took him from the besieged Bosnian capital of Sarajevo and the town of Tuzla to Belgrade, the Serbian and Yugoslav capital, where he met with Slobodan Milosevic. He is scheduled to meet with both Clinton and Christopher on Monday to report on his findings. At that meeting, Biden is expected to make a powerful case both for American military strikes and for a lifting of the international ban on arms for the Bosnians.

“I could find no one among the Bosnians who did not think that Bosnia could defend itself if given the means and supported by air strikes against Serb artillery,” Biden told The Times on Friday.

Times staff writers Doyle McManus and Stanley Meisler in Washington and John J. Goldman at the United Nations contributed to this report.