An Australian military plane dropped food and supplies to people hiding in the hills of East Timor today as international peacekeeping troops geared up to move into the ravaged Indonesian territory as early as Saturday.

The Australian Air Force C-130 dropped 20 pallets of rice and blankets after receiving permission from Indonesian authorities, who had originally opposed dropping food until peacekeepers were on the ground to help distribute it. Ross Mountain, the United Nations' humanitarian coordinator for the East Timor crisis, said Indonesian President B.J. Habibie approved the delivery today.

"It was a matter of working out the details of an overflight by a military aircraft of another country," Mountain said. More flights may follow, provided the aircraft are not fired upon or otherwise challenged by the militias who have terrorized East Timor for weeks. The violence has prompted thousands of people to seek refuge in the hills, and Indonesia acceded to an Australian-led multinational peacekeeping force this week.

As the peacekeeping troops continued preparing for their mission, 250 Brunei-based British army Gurkhas landed here in Darwin to join the advance team of the planned 7,000-member force.

At least 11 other countries are expected to contribute to the force, which will launch a coordinated air and land incursion into East Timor. Under an authorization passed Wednesday by the U.N. Security Council, the forces will be permitted to shoot to kill to restore order.

"Let there be no misunderstanding. This is going to be a difficult and demanding task," said Adm. Christopher Barrie, chief of the Australian Defense Forces.

The biggest uncertainty nagging military planners is the reaction of the Indonesian military, which opposed independence efforts in East Timor. It recruited and armed 13 militias in a failed attempt to disrupt the Aug. 30 referendum in which East Timorese voted overwhelmingly against autonomy within Indonesia, and therefore for independence.

But Barrie noted that, under orders from Habibie, the Indonesian military cooperated in the evacuation of 2,538 East Timorese and U.N. personnel from the besieged U.N. compound in Dili, the territorial capital. He said he hoped for "good cooperation" from the military.

East Timor's military commander, Maj. Gen. Kiki Syahnakri, promised his 26,000 soldiers and policemen would withdraw when the peacekeepers arrived, according to reports from Jakarta, while Indonesian Defense Minister Gen. Wiranto seemed to send a different signal, saying his troops would remain to ensure that the multinational force remains neutral.

Wiranto's message has been seen as a careful use of code words; the government in the past accused the United Nations, which supervised the independence referendum and will play a key role in East Timor's transition to independence, of bias in favor of the separatists, and Wiranto said some of his men consider the anti-independence militiamen as their "brothers in arms."

The militias, which have burned, killed and looted in East Timor since the referendum results were announced Sept. 4, also are a worry for the operation's planners. But sketchy reports from Dili today suggested the capital is quieter, and the militiamen may be leaving. And a spokesman for the U.N. mission in Dili said there were reports of military trucks moving out.

Still, Maj. Gen. Peter Cosgrove, who will lead the multinational force, bluntly warned the militias today to "surrender their arms, return to their homes, or leave Timor."

The violence has forced at least 200,000 of the 800,000 East Timorese to flee their homes. About half of the displaced are in camps in western Timor or have gone elsewhere in Indonesia. But thousands are thought to have fled into the East Timor hills to escape the militias, and they are reported to be without food.

Australia is leading the multinational force despite complaints from some Indonesian officials about the high profile of its southern neighbor. Jakarta has chafed at Australia's support for East Timor and today canceled a security agreement between the countries "because of the attitude and actions of Australia, which are no longer consistent with the spirit and letter of the agreement," said Feisal Tanjung, Indonesia's coordinating minister for security.

Dewi Fortuna Anwar, a senior adviser to Habibie, said in a televised interview that caused consternation in Australia: "There is a very, very strong feeling of animosity, rightly or wrongly, toward Australia. If the U.N. peacekeeping force is made up of Australians, they will be singled out" for attack by pro-Indonesian forces.

Prime Minister John Howard has warned that the mission might entail casualties.

And organizers of the force said they expected the Indonesian military will be there when the multinational troops arrive, despite its role in abetting the militias and the violence in East Timor.

The renowned British Gurkha troops, who have been in Kosovo and have fought in almost every other conflict involving Britain, are joining the peacekeepers because they are "climatized," according to Brig. David Richards, a top planning officer in the force's British contingent.

"It's very humid here; it's very hot," he said. "To bring in troops from the outside to do the job and expect them to operate fully from day one is not possible. We are using the Gurkhas because they are extremely good in operating in this environment."

About 200 U.S. military personnel will be assisting with the peacekeeping mission, and Barrie said he also expects troops, military support and aid from New Zealand, Canada, Portugal, France, Brazil, Italy, the Philippines, Malaysia, Singapore and Thailand.

Australia will provide the largest contingent of troops, about 4,500, Barrie said.

The mobilization of the multinational forces has electrified Australia, and the port city of Darwin, on the northern coast, is bustling. Residents have gone down to the port to see the assembling of a mini-armada: the British missile ship Glasgow is tied up beside an Australian naval vessel, the Adelaide, both docked in front of the sleek, streamlined Australian troop-carrying catamaran, the Jarvis Bay.

"It's a terrible thing that's happened in East Timor," said Gary Page, a taxi driver. "But it's really put Darwin on the map. There's a whole lot of bustle in town, and people who probably never heard of Darwin are hearing of it now."