CANBERRA The United Nations urged Australia on Monday not to use force against 217 asylum seekers refusing to leave a navy vessel off the Pacific Island of Nauru.

In a bid to crack down on rising illegal immigration, Australia has started to intercept boats, carrying asylum seekers, before they reach Australia and take them to alternative destinations, for their claims for asylum to be processed.

The navy troop carrier, Hmas Manoora, picked up 670 asylum seekers in two separate boats nearly four weeks ago and the government has brokered a costly deal for Nauru to take them, building a makeshift camp on the tiny island to house them.

But a group of mainly Iraqi asylum seekers are refusing to disembark, with no guarantee of success for their refugee applications and no timetable for their stay on the sweltering, barren island.

"We would prefer not to see force used against asylum seekers," a spokeswoman for the UN High Commissioner for Refugees told Reuters.

"We expect them to be treated in a humane way consistent with international refugee principles and laws."

Australia's conservative government has received strong public support for its new hardline against asylum seekers ahead of a tough year-end election. It has turned away five boats, carrying about 1,000 asylum seekers in the past month.

Public discontent over boatpeople has risen as the number of illegal entrants increased to 5,000 a year -- a small number internationally but a jump from a few hundred five years ago.

About 260 asylum seekers stranded on two Indonesian boats off the remote Australian outpost of Ashmore reef for almost two weeks were picked up by the Hmas Tobruk at the weekend.

Immigration Minister, Philip Ruddock, refused to say where they were heading.

"They won't be coming to the Australian mainland," he said. The boat people were expected to be taken to Australia's Indian Ocean territory of Christmas island -- with laws expected to be approved in the national Parliament on Monday removing several remote Australian outposts from its migration zone.

The change will mean boat people arriving at places like the Cocos, Christmas and Ashmore islands -- popular landing spots for migrants -- will not be able to get an Australian visa, normally issued while refugee claims are processed.

Ruddock flew to Christmas island at the weekend to tell residents the government planned to build a long-requested sports hall on the island at a cost of up to a$10 million (U.S.$4.8 million) -- which would double as a processing center.

The government is continuing to seek alternative locations for boat people who pay people smugglers for passage to Australia.

Foreign Minister, Alexander Downer, said talks with the Pacific Island of Kiribati had yielded a preliminary agreement to use one of the country's islands as a new off-shore processing territory.