Friday September 1 5:55 p.m. EDT

U.N. Force Commander Meets Mladic

BELGRADE (Reuter) - The United Nations commander in former Yugoslavia, General Bernard Janvier, met Bosnian Serb military chief Ratko Mladic Friday, diplomats and United Nations officials said.

The meeting in the border town of Zvornik, came after the U.N. and NATO called a pause in their bombing campaign against Bosnian Serb targets.

``The meeting is to inform Mladic of the demands for halting the joint U.N.-NATO operation against Bosnian Serb positions and installations,'' said U.N. spokesman Alexander Ivanko in Sarajevo.

The meeting paused almost immediately after starting for Janvier to check Mladic's claims that NATO was still bombing several Serb positions after an announced pause in operations.

``Janvier checked, came back and told Mladic ``Not true' and talks resumed in earnest,'' an envoy said.

The talks are expected to last well into the night which might force Janvier to spend the night in Belgrade instead of going straight to Zagreb.

The U.N. has demanded the Bosnian Serbs pull all their heavy weapons out of range of Sarajevo and stop threatening other ``safe areas'' as a condition for permanently ending the massive NATO military campaign against them.

Diplomats said Janvier would demand maximum concessions by the Serbs, including reopening of the Sarajevo airport and supply roads -- ``blue routes'' into the besieged city.

There had been no formal Bosnian Serb army response to the U.N. demands, made by letter, although Greek defense minister Gerasimos Arsenis said Mladic was ready to pull back the guns.

Diplomats said the meeting would give the Serbs an opportunity to reply in person to the U.N. demands but the Bosnian government fears the U.N. high command is looking for a way to let the Serbs off the hook.

Both Mladic and Bosnian Serb political leader Radovan Karadzic have made defiant public comments, refusing to be cowed by the arsenal ranged against them.

Bosnian Serb parliament speaker Momcilo Krajisnik told Bosnian Serb Television the Serbs would never surrender Serb-held parts of Sarajevo.

NATO launched the largest military assault in its 46-year history Wednesday to punish the Serbs for a mortar bomb attack on Sarajevo that killed 37 people.