ZAGREB, Croatia (AP) _ A leader of Croatia's ethnic Serb minority claimed Monday that his people had been betrayed by Serbia's president and would rather ''die honorably'' than join an independent Croatia.

The remarks by Mile Paspalj, speaker of self-declared parliament in the enclave of Krajina, reflected the determination of some ethnic Serbs in Croatia to resist U.N.-supervised peace efforts. That stance has put them in growing conflict with Serbian President Slobodan Milosevic, their former ally.

Milosevic, fearing that Serb-led forces could not defeat a Croatia backed by Western Europe, agreed to the U.N. accords in December. By then thousands of people had died in battles between Croatian guards and Serb-led forces.

The peace plan calls for U.N. peacekeeping patrols throughout Croatia. It also demands ethnic Serb paramilitary units disarm and the Serb-led federal army withdraw from Croatia.

But many ethnic Serbs are nervous that the 12-nation European Community, which granted Croatia and Slovenia diplomatic recognition last week, wants to force them to accept Croatian rule.

''An overwhelming majority of people in Krajina would rather die honorably than be a national minority in a fascist state of Croatia,'' Paspalj was quoted by the Belgrade-based Tanjug news agency. ''Milosevic is now not working in a way desired by an overwhelming majority of the Krajina people.''

Leaders of Croatia's 600,000 ethnic Serbs say they fear persecution in an independent Croatia, often noting the mass killings of Serbs by a Nazi puppet regime during World War II.

Croatia has made assurances to the EC it will respect the rights of ethnic minorities.

A U.N.-brokered truce appeared to be holding for the 18th day Monday despite some serious clashes over the weekend.

Two Croat soldiers were reported wounded in separate battles Monday in eastern Croatia.

On Sunday, five Croatian soldiers and one Serb fighter reportedly died, and three federal army soldiers were reported killed Saturday.

Belgrade TV reported Croatian forces fired 40 mortar shells overnight at federal positions near Nova Gradiska on the central front.

''Unless the Croatian provocations cease immediately, the Yugoslav army will have to do everything to protect the lives of its soldiers,'' Col. Ratko Lepir was quoted by the TV newscast as saying.

Croatian commanders, meanwhile, sent a protest to the Yugoslav Army accusing it of violating the cease-fire, Zagreb radio reported late Monday. It cited several alleged federal attacks, including heavy machine-gun fire on a funeral procession in Posedarje near the coastal town of Zadar.

None of the claims could be independently confirmed. Both sides have repeatedly accused each other of violating the truce, but it has been much more effective than 14 previous cease-fires.

About 50 U.N. observers are monitoring compliance with the truce. If it holds, the United Nations plans to send up to 10,000 peacekeepers.

Meanwhile, there were signs of cooling relations between Slovenia and Croatia, which have been allies because both declared independence on June 25.

In Ljubljana, Slovenia, Foreign Minister Dimitrij Rupel called relations with Croatia ''complicated and difficult,'' Tanjug reported.

He said differences existed over access to Adriatic ports and ownership of $600 million in a Ljubljana bank branch in Zagreb. Croatia and Slovenia are also trying to draft a trade pact.