In his first full briefing since the conflict started, Lieutenant-General John Reith said it could take that time to repair the devastation caused by Serb forces.

He said: "When the Serbs evicted the people from Kosovo they did tremendous damage, particularly to the outlying villages and have gutted most of the homes.

"That will take time to repair and my experience from Bosnia was that even two years later, many of the houses had not been repaired. There's a huge logistical problem there in getting the materials in and getting the expertise to do that work."

He also said that an attempt to move more than 30,000 refugees away from the northern-Albanian town of Kukes would begin in the next few weeks.

The general, commander of Nato's humanitarian relief operation known as Allied Harbour Albania Force (AFOR), said Serb shelling of the refugee camps there was a possibility and if that happened, it could cause a humanitarian disaster.

Kukes refugees face danger

Kukes, a former mining town near the Albanian-Kosovo border, has been the main reception centre for over 400,000 Kosovo Albanians who have fled the province since late March and is still home to more than 130,000, many of them living in makeshift shelters and tent cities.

"We are working with the UNHCR on a plan to effectively close the tented camps in Kukes," he said.

Hundreds more refugees crossed into Albania at the main Morina crossing point north of Kukes on Friday and several thousand more were on their way, officials of the Organisation for Security and Cooperation in Europe (OSCE) said.

(Click here to see a map of the most recent refugee movements)

Serbian forces have repeatedly shelled Albanian border districts further north, apparently in attacks against strongholds of the separatist Kosovo Liberation Army. KLA units have also been spotted near Kukes.

"There is evidence now of KLA activity in the Kukes area," Gen Reith said. "I do not want a humanitarian disaster where the Serbs shell one of the refugee camps. We would have a mass casualty situation."

Hashim Thaci: People are living rough

Asked whether the road improvements and Kukes evacuation plan may also be designed to assist any deployment of Nato forces inside Kosovo, Gen Reith declined to comment, insisting his mission was purely humanitarian.

Meanwhile, the leader of the Kosovo Liberation Army, Hashim Thaci who appeared in public for the first time in two months - said he believed that 600,000 civilians were now living in the open in Kosovo in extremely difficult conditions.

He said the KLA was providing them with food, medicine and financial help.