The World Food Programme (WFP) has had two planes on standby since Saturday, but they have not been able to get off the ground because of the volume of Hercules aircraft traffic involved in transporting the multi-national force to the territory.

"It's simply a question of logistics," said David Wimhurst of the UN Assistance Mission to East Timor (Unamet).

Vicky Horne of Oxfam talks to BBC World Service, Newshour: "It's absolutely horrific"

Since Thursday, UN agencies have only managed to send four flights - dropping around 30 tonnes of rice, high-calorie pre-packaged meals and blankets to refugees hiding in the island's mountainous interior.

Mr Wimhurst said delays on Sunday and Monday were caused by "Indonesian sensitivity" over the deployment of the multinational UN force.

The UN High Commissioner for Refugees, Sadako Ogata, said she had won a commitment from Indonesian President BJ Habibie to allow a resumption of the flights.

Click here to see a map of the main refugee camps in East and West Timor

As many as 190,000 people are still believed to be hiding in the mountains of East Timor, in conditions described by aid agencies as "severe".

Sadako Ogata: "Much more complicated than Kosovo"

The Red Cross says it will step up its operation in the territory on Wednesday - with an emphasis on providing medical care, water and sanitation.

"The people are in a terrible position," said Sri Endah Wahyu, International Committee of the Red Cross (ICRC) spokeswoman in the Indonesian capital, Jakarta.

"A mobile hospital will soon be arriving from Australia," she said, adding that though the ICRC office in Dili had been ransacked by militiamen, its warehouse had not been damaged or looted.

Exiled in West Timor

Mrs Ogata, the UNHCR chief, has been lobbying the Indonesian government to allow her agency to establish a presence in West Timor, where as many as 200,000 refugees are living in make-shift camps.

More refugees are still trying to leave East Timor

"Indonesian police can be trusted to do everything to make their stay over there safe and secure," she said after her two-hour meeting with Mr Habibie in Jakarta.

Earlier, Mrs Ogata visited three refugee camps near the border between East and West Timor, and in the main West Timorese town, Kupang.

She said the "most important thing" was that the refugees were given the choice of returning to East Timor or being resettled in Indonesia.

"It is more complicated than Kosovo, which was mostly a return. These people will vote with their feet by deciding where to go," she said.