The top U.N. commander in Bosnia traveled to battered northwest Bosnia Wednesday to try to salvage a hard-won truce that is being threatened by escalating attacks.

If Lt. Gen. Sir Michael Rose fails to silence guns in the Bihac region, prospects would be dim for setting up the longer, four-month truce between the Muslim-led government and Bosnian Serbs that Jimmy Carter brokered last week.Serbs from neighboring Croatia and renegade Bosnian Muslim fighters have joined forces to dislodge the Bosnian government army from the U.N.-designated "safe area."

The Croatian Serbs and Bosnian Muslim rebels are are not party to the weeklong cease-fire agreement between the Bosnian Serbs and the Muslim-led Bosnian government that took effect Saturday. Still, the government has warned that the attacks could scuttle the longer truce.

The government and the Bosnian Serbs - the two main combatants - agreed to the weeklong cease-fire to negotiate the details of the four-month truce.

Rose's helicopter touched down at Coralici, a small town north of Bihac, where a Bangladeshi U.N. battalion is based.

He was to see Gen. Atif Dudakovic, commander of the Bosnian government's hard-pressed 5th Corps; commanders of the Bangladeshi U.N. battalion there; and Fikret Abdic, leader of the renegade Muslims who have declared regional autonomy in the Bihac pocket.

It was unclear if the meeting with Abdic would take place. The Bosnian Serb news agency SRNA reported that fighting intensified today in the area.

It said the fiercest battle took place south of Velika Kladusa, in the very north of the Bihac pocket, "where Abdic's troops are advancing toward Bihac."