1 A warning by Bosnian Serbs on Friday that any renewal of the war in Croatia would draw them into the fray turned up Balkan tensions another notch.
2 If Croatia attacks Serb-held parts of the republic, 'we will defend it,' Bosnian Serb leader Radovan Karadzic told Associated Press Television. 'If they squeeze . (the Serbs) in Croatia, we may unite and defend ourselves as a united country.'
3 The warning, uttered just months before the planned departure of the thousands of peacekeepers who have enforced a brittle truce in Croatia for three years, came on the heels of United Nations cautioning of an upsurge of violence in both Croatia and Bosnia barring new peace talks.
4 The warning on Bosnia was uttered by Yasushi Akashi, the top U.N. official in former Yugoslavia; the fears about Croatia by an aide, Michael Williams.
5 Croatian President Franjo Tudjman has served notice to 12,000 peacekeepers separating his forces from rebel Serb units that they must go after their mandate expires March 31.
6 The international community is attempting to get Croat and rebel Serb agreement on a plan that would reintegrate Serb-held lands captured in 1991 back into Croatia in exchange for rights guarantees -- and in some cases substantive autonomy -- for the Serbs.
7 But the Serbs are refusing even to discuss the plan unless the peacekeepers stay. Their leader, Milan Martic, said Friday such talks were 'senseless' and warned that Bosnian Serbs and the Yugoslav army would back his side in any fight with Croatian troops.
8 Croatia, initially supportive of the plan, also said it was unacceptable Friday. Smiljko Sokol, a Tudjman advisor, told reporters it went too far in granting Serbs near autonomy in some regions.
9 Williams, asked about the situation in Croatia, said it was 'very serious and was reaching a dead-end.'
10 Some analysts express concern that Tudjman's decision to expell the peacekeepers could mean he has reached an understanding with Serbia's president, Slobodan Milosevic. Under such a deal, Croatia would stop supporting Bosnian troops against the Serbs in Bosnia in exchange for a Serbian guarantee of non-interference in Croatia.
11 That would mean an end to Bosnia's troubled Croat-Muslim federation and almost certain defeat of Muslim-led government troops. Bosnia is sandwiched between Serbia and Croatia.
12 U.S. Assistant Secretary of State Richard Holbrooke was to hold weekend talks in Germany on bolstering the Croat-Muslim federation.
13 The federation, backed by the United States, is 10 months old and managed to end bitter fighting between Bosnian Croats and Muslims, who were allied against the Serbs at the outset of war 34 months ago.
14 But the two sides have done little more than institutionalize a cease-fire.
15 'Negative events on the federation would have a deleterious effect on an already dangerous situation,' Holbrooke told reporters Thursday at the State Department in Washington. 'We're at a pretty critical time in the situation in the Balkans.'
16 Akashi voiced similar pessimism on Bosnia.
17 'Throughout Bosnia-Herzegovina, confrontation lines remain dangerously close, and armed forces continue their preparations for wider conflict,' Akashi warned. Without 'immediate steps to strengthen the cease-fire, the threat of renewed conflict is real,' he said.
18 'All involved must now make . a concerted effort to solve the conflict in Bihac,' Akashi said in a written statement. Fighting in that northwestern region, particularly around Velika Kladusa, headquarters of rebel Muslim leader Fikret Abdic, has vexed international efforts to anchor a month-old, Bosnia-wide truce.
19 Abdic's forces and rebel Serbs from neighboring Croatia are not party to the agreement, which was designed to halt fighting and separate forces as a prelude to resuming peace negotiations.
20 But international efforts to get negotiations started collapsed last week due to Serb intransigence. The Bosnian government, impatient with U.N. inability to halt fighting, has warned the truce could collapse entirely.
21 U.N. officials expressed concern Thursday about an apparent increase of Croatian Serb tanks, artillery and troops in the Bihac region. Most blame for the fighting lies with them, Williams said.
22 Overnight, the Bihac area was reported relatively quiet. But two people were killed and six wounded Thursday in the government-controlled town of Buzim, 30 kilometers (20 miles) northwest of Bihac. There was no word on who fired.

A warning by Bosnian Serbs on Friday that any renewal of the war in Croatia would draw them into the fray turned up Balkan tensions another notch .
any renewal of the war in Croatia
What would cause a renewal of this war?