UN High Commissioner Sadako Ogata said the cash shortage could seriously set back efforts to help the estimated 750,000 refugees in Albania, Macedonia and Montenegro.

She has asked European governments for more help, saying she needed double the $71m already raised.

So far efforts to get refugees in Albanian and Montenegro to move voluntarily away from border areas with Serbia have proved unsuccessful.

Jacky Rowland in Belgrade: UN agencies want to return to Kosovo

A delegation of United Nations relief agencies, including UNHCR and UNICEF, has been carrying out an assessment mission to Yugoslavia.

The agencies have been discussing with local officials ways of expanding their activities in the whole of Yugoslavia, including Kosovo.

UNHCR plea

Fergal Keane: "They're being asked to go South in the promise of safety"

Ms Ogata has asked European countries to bear a greater part of the financial burden of taking care of the refugees, calling the Kosovo conflict "a European tragedy".

Ms Ogata said: "Improving camp conditions as summer approaches is a top priority.

"In the meantime, winter is only a few months away and we need to prepare for that too. Refugees cannot stay under flimsy tents when winter comes."

Tensions in the camps

Many do not want to start another journey

The Former Yugoslav Republic of Macedonia has criticised the UNHCR for being slow and disorganised in its efforts to deal with the crisis.

"We are trying to collaborate with them but unfortunately they don't understand how sensitive the situation is", Macedonian Foreign Minister Aleksandar Dimitrov said.

Macedonia is faced with serious economic and social disruption because of the huge influx of Kosovo Albanians - equal to 10% of the population.

The UNHCR says the last significant arrivals in Macedonia were a week ago while nearly 40,00 of a total of 240,000 have been received in third countries.

A UNHCR official discussed the possibility of introducing international liaison and police forces into Macedonian camps after rising tensions this week led to protests in two camps on Monday.

The agency is trying to move some 60,000 refugees to camps in Albania, although it admits that will mean the pressure will mount in the Albanian camps.

Albania itself wants several thousand of its 400,000 refugee population to move away from the northern city Kukes, 18km from the Serbian border.

Frank Gardner in Kukes: Advice to refugees is "Don't venture out at night"

UN official Dennis McNamara in Tirana said it was not "safe for them to stay on that highly contested border". But many refugees are reluctant to move further away from Kosovo, and be separated from loved ones they have left behind.

Security for 9,000 refugees at a camp in northern Albania run by an Arab government has been stepped up after attacks by Albanian civilians.

Workers at the United Arab Emirates camp have also completed digging a large number of covered trenches, in case of shell fire from Serb forces across the border.

Meanwhile at a camp run by Médecins Sans Frontières near Kukes, it is reported that only 200 from several thousand refugees attended a meeting held to persuade refugees to leave.

An Albanian government official is quoted as saying the refugees will have to move or "we will close the camps and people will have nowhere to stay".

Contact in Belgrade

Aid agencies are anxious to increase the scope of their activities in the whole of Yugoslavia to meet what with what they believe is an increased need there.

The UN delegation currently in Belgrade has been holding consultations with Foreign Ministry officials, the Yugoslav Red Cross and other local aid organisations. A more detailed mission will follow next week.