UK aid agencies are considering a joint fund-raising appeal for victims of the Indonesian earthquake, as relief teams arrive in the region.
Thousands have died and been injured in the quake
The Disasters Emergency Committee, which represents 13 UK agencies, said a decision would be made within two days.
International Development Secretary Hilary Benn has pledged £1m in aid to the Red Cross on top of £3m already promised to the UN effort.
At least 5,700 people were killed and thousands hurt by Saturday's quake.
The quake, measuring 6.2, flattened buildings in a densely-populated area near the city of Yogyakarta on the southern coast of Java.
An estimated 20,000 people have been injured, according to latest reports.
Oxfam, whose workers arrived soon after the quake hit, said vital supplies had reached thousands, adding that its immediate objectives included restoring water supplies.
Meanwhile, two Department for International Development (DFID) humanitarian experts have arrived in Indonesia and have visited the Bantul area.
The department's office in Jakarta, Indonesia, has agreed the Forestry Programme office in Yogyakarta can use DFID funds to buy supplies such as blankets, drugs and water.
A DFID spokesman said: "We will respond immediately to requests when they come in.
"Our latest understanding is that aid is getting through but, obviously, it is going to be a big operation."
The department says an estimated 25,000 houses were destroyed, and a further 45,000 damaged.
Meanwhile, DEC chief executive Brendan Gormley said a decision would be made in the next two days over whether to launch a joint fund-raising appeal.
He said talks were being held with member agencies and the Charity Commission to see if cash donated for the tsunami could be used.
Relief workers have said hopes are fading of finding more survivors, despite the fact that help is getting through.
Save the Children, which dispatched a UK team to the scene in Java, is working to deliver hygiene kits to 1,000 affected families while 30 boxes of games and toys, including sports equipment, are heading for Yogyakarta.
The additional £1m in UK aid is in response to an appeal for £6m from the International Federation of Red Cross and Red Crescent Societies. Save the Children has also launched an appeal.
The Indonesian ambassador to the UK, Marty Natalegawa, has praised the reaction of the British government.
"What's even more appreciated is the response of the British public," said Dr Natalegawa.
"I have been receiving many calls from the public asking how they can be of help."
The World Health Organisation has provided emergency medical kits for 50,000 people and supplies to support 600 operations.
Measures taken by the Indonesian government include setting up 18 field hospitals and deploying more than 200 medical staff.
British businessman Geoffrey Pomeroy, who lives in the devastated area of Bantul, said night-time looting was taking place at houses damaged by the quake, prompting many to return to their homes.
"Even though they are all completely smashed in, there are valuables inside," he said.
Mr Pomeroy, managing director of Exeter-based PT Asia Trade Line, opened the company's warehouse to give shelter to about 120 people who were made homeless.
Prime Minister Tony Blair has sent a message to President Susilo Bambang Yudhoyono, offering condolences on behalf of the British people and backing up the offer of assistance.
The Queen has also sent a message of sympathy.
And the Indonesian Embassy in London has opened a book of condolence, which has been signed by Deputy Prime Minister John Prescott, at its building in Grosvenor Square, central London, until Thursday.
Mr Prescott is co-ordinating the UK's response to the disaster through Mr Benn.
Anyone wishing to make a donation to help victims of the Java earthquake can call Plan International on 0800 526848.