Serbia Says It Favors a Cease-Fire : Yugoslavia: It apparently bows to European pressure to halt the ethnic bloodshed in neighboring Croatia.

Apparently bowing to European pressure, Serbia said Saturday that it would seek a cease-fire to halt ethnic bloodshed in the neighboring Yugoslav republic of Croatia and would accept the presence of foreign civilian observers to enforce it.

The immediate reaction among European observers and Western diplomats on a sultry and rainy Saturday night was one of caution. “The proof is in the pudding. Let’s wait and see,” said one diplomat.

Talk of peace contrasted sharply with passions that exploded at the airport in the Croatian capital of Zagreb on Saturday in a gun battle between Croatian forces and Yugoslav army troops over a planeload of arms.

Serbia’s announcement came without preface as part of the Belgrade evening television news on the eve of a deadline set for today by foreign ministers of the 12 European Community countries. They had demanded that Serbia, Yugoslavia’s largest republic, agree to a peace conference and permit stationing of European monitors between armed and angry Serbian and Croatian communities in Croatia.

“An agreement on a cease-fire will be achieved,” said Serbian Foreign Minister Vladislav Jovanovic, promising that “it will be effective” and that Serbia would also accept outside observers.

“Serbia has no reservations except that we continue to consider that the composition of the (monitoring) teams must be civilian,” he told an interviewer.

That Serbia’s long-awaited response to Europe’s demand came almost offhandedly from a second-line official instead of hard-line Serbian President Slobodan Milosevic clouded its impact for some observers here Saturday.

In demanding an end to the violence in Croatia that has claimed about 300 lives this summer, the European Community is seeking to head off open civil war in this Balkan nation of 24 million riven by bitter ethnic hatreds.

Croatia, which, with Slovenia, asserts its independence from the tattered Yugoslav federation, had previously accepted the proposal advanced by Europe’s most powerful and richest nations. So had other restive Yugoslav republics and the powerless federal government, leaving truculent Serbia the odd man out.

Observers from the European Community have successfully monitored a cease-fire in Slovenia, but Croatia, a republic of 4.7 million people, has been stalked by accelerating violence between Croatian nationalists and guerrillas of the 600,000-member Serbian minority there supported by the Serbian-dominated Yugoslav army.

While apparently accepting the EC terms Saturday, the Serbian foreign minister rejected what he called its “condemnation of the Serbian people in Croatia, which is completely untrue and for us absolutely unacceptable.”

For its part, Croatia, which has threatened to declare war on the Yugoslav army as an occupying power, Saturday again endorsed the Community’s call for peace talks but stressed that its independence is not negotiable, the Croatian news agency Hina reported after a meeting of the Croatian government.

In Zagreb, fighting flared at the airport after the Yugoslav air force intercepted two planes suspected of smuggling arms and forced them to land. One was searched and allowed to leave, but the second, a Uganda Airlines 707, contained 19 tons of weapons apparently intended for Croatian forces, the news agency Tanjug reported.

While the plane was being guarded by Yugoslav troops, the agency said, Croatian militia attacked the control tower, blocked the airport approach roads and fired mortars at the jet in an apparent attempt to destroy it.