Almost 500,000 refugees are estimated to have fled the troubled Yugoslav province.

Up to 300,000 have arrived in Albania, which was already the poorest country in Europe.

Another 130,000 are in Macedonia and a further 150,000 are believed to be queuing at the Macedonian border. Neighbouring Montenegro has taken in 35,000.

At the launch of the Disasters Emergency Committee (DEC) appeal on Tuesday, an aid worker who has just returned from Albania said people were dying at the rate of two an hour.

Ama Annan, of Christian Aid, has just returned from Albania: "In the space of 90 minutes I saw three people die"

The appeal aims to raise funds to meet the urgent need for food, shelter, medicines, blankets, mattresses, water and sanitation equipment.

On Tuesday the Chancellor of the Exchequer, Gordon Brown, extended the Millennium Gift Aid scheme to cover donations made to the DEC appeal.

Money from the taxman

It will mean gifts of £100 will be boosted by an extra £30 from the Inland Revenue.

Gordon Brown: "The crisis has touched many Britons"

Mr Brown said: "Everyone has been moved by the plight of the people of Kosovo.

"This change to the Millennium Gift Aid scheme will enable taxpayers in the UK to do their bit to help and ensure government money backs up their donations."

The 12 charities teaming up under the DEC umbrella are the British Red Cross, Cafod, Care International, Children's Aid Direct, Christian Aid, Help The Aged, Concern Worldwide, Merlin, Oxfam, Save the Children, Tearfund and World Vision.

The BBC's Susannah Reid: "British efforts to help refugees are moving into top gear"

Banks will be handling donations to the appeal free of charge. Television, radio and newspapers are offering free advertising and BT is supplying 3,400 phone lines for credit card donations.

Special televised appeals will be made on BBC, ITV and Channel 4 at 1825 BST.

Christian Aid spokeswoman Ama Annan, who arrived from Albania late on Monday night, said: "I was at a border crossing near the town of Kukes two mornings ago.

Refugees are being airlifted to Nato member states

"While we were there, in the space of one-and-a-half hours, we saw three people die."

'Weak and traumatised people'

She said: "People are very weak and traumatised from the experiences they've had on the other side of the border."

Ms Annan said the refugees were hungry, thirsty and in need of shelter, but she said the Tirana government had a policy of bussing the Kosovars to central and southern Albania as quickly as possible.

The appeal aims to raise funds for emergency aid

She said the journey from Kukes to Tirana took 10 hours, on very poor roads, and this was worsening the refugees' condition.

Ms Annan said foreign agencies were co-operating on the ground but the situation was changing by the hour.

She said: "The big difference between Albania and Macedonia is that the Albanians welcome the refugees.

"They are appalled by the atrocities and they want to help.

'Albania is a pauper nation already'

"But it is the poorest country in Europe and they do need support."

Julian Filochowski, of Cafod: "It's as if five million homeless people had suddenly arrived in Kent"

Cafod has mobilised resources in Albania, Macedonia and Montenegro while a Christian Aid emergency team is due in Tirana later this week.

Care International has teams in Macedonia and Albania, and Children's Aid Direct has provided 40 tonnes of material aid, 140 tonnes of food parcels, 150,000 sets of children's thermal underwear and 5,000 family hygiene packs.

Help the Aged and its international partner HAI are developing a programme to assess and deal with the needs of older refugees.

Merlin is aiming to address deteriorating health situations if and when they arise, such as epidemics of measles, meningitis, TB and polio.

Aid flights

Sam Younger, of Christian Aid: "It is clear this is not going to be a short-term issue"

Oxfam's first flights landed on 2 and 3 April, taking with them £127,000 worth of aid and enough water and sanitation equipment to help about 70,000 refugees in Skopje and Tirana.

Save the Children is providing children's survival kits, clothing, plastic sheeting, water containers and other essential items.

Tearfund is working with local partners to provide aid to the refugees and World Vision delivered aid including food and non-food items particularly for mothers and babies.

Donations can be made to the DEC Appeal by credit or debit card by calling 0870 6060900.

Donations can also be sent by post to: Kosovo Crisis Appeal, PO Box 999, London, EC4A 9AA.

A credit card donation line via the DEC Website should go live on Tuesday.