The Organisation for Security and Co-operation in Europe has warned that it willhave to reconsider its ceasefire monitoring mission in Kosovo if the bloodshed and violence there escalates.

The OSCE, which has about five-hundred unarmed monitors in the troubled Serbian province, gave the warning as Serbian security forces and ethnic Albanian guerrillas clashed for a fourth successive day.

It blamed both sides for the violence The two sides exchanged mortar and heavy machine-gun fire for much of Sunday.

However, the top international official in Kosovo, William Walker, told the BBC that a ceasefire had been going on since late afternoon, and that international monitors had managed to get two wounded fighters out.