More than 30,000 people are being looked after at the Brazde camp near Skopje, and more are arriving every day.

But the latest refugee influx has cast doubt on whether the aid agencies will be able to cope when the army moves out.

A British Army spokesman said the army was leaving the camp because aid agencies "have got their act together", and are now "much better placed to look after the refugees than the army".

BBC Correspondent Jonathan Charles: "This camp could collapse into chaos"

He said the army's help had always been a short-term measure, which had been useful for laying water pipes, digging latrines, putting up tents and offering basic medical care.

"Now the army can go back to being ready to enter Kosovo once a peace agreement is reached, to help enforce it in full," he added.

Major Ian Seraph said: "We will be sad to leave, but leave we must.

"We will keep a weather eye on the condition of the refugees and if we need to help, we can come back."

The camp requires 70 tonnes of food every day which is unloaded by soldiers.

But Mark Mathias of Supreme Food Service, which has been supplying the basics, said aid agencies lacked the army's field kitchens which have been vital for feeding the refugees.

"It will be a big challenge for them to feed that number of people," he said.

As the camp grows ever bigger, even humanitarian organisations have qualms.

Paula Ghadini of the UNHCR said: "If there is a huge influx we will definitely need the added logistical support of Nato."

BBC Correspondent Jonathan Charles said: "This camp could collapse into chaos without the support of the British Army."

Thousands of refugees have crossed into Macedonia and Albania in the last few days

Thousands of ethnic Albanians crossed over into Macedonia and Albania on Thursday, and more were expected on Friday, in what observers believe may be a final push by Yugoslav forces to rid Kosovo of its ethnic Albanian population.

Both countries now have around 435,000 refugees.

People arriving on Thursday told humanitarian workers at the border that thousands more refugees were backed up behind them on the other side of the border, hoping to cross over to safety.

British Army soldiers will soon move out

Macedonian President Kiro Gligorov said on Thursday: "We have again been confronted with the arrival of a large number of refugees ... but Macedonia has only limited means (to cope with the influx) which were saturated long ago.

Macedonia is seen as one of Kosovo's most vulnerable neighbours, and President Gligorov accused Belgrade of deliberately seeking to destabilise Macedonia by provoking an influx of refugees.