Australia's plan to send asylum seekers to Malaysia struck a legal hitch today, with a court delaying the transfer of the first group to the Asian nation pending another hearing.

The decision came after lawyer David Manne from the Refugee and Immigration Legal Centre sought an injunction stopping the removal of the group, arguing that Australia did not have the right to deport boatpeople.

"This is about life or death matters and our clients are challenging the government's power to expel them to Malaysia where they fear they will not be protected and they are at real risk of harm," Manne said ahead of the hearing.

Australia plans to send up to 800 asylum seekers to Malaysia in return for accepting 4,000 registered refugees from that country over four years under a deal designed to stop boatpeople from landing in Australia.

Manne said he was representing 41 of the 55 asylum seekers who arrived by boat in Australia last week and who had been expected to begin leaving for Malaysia on Monday.

"Australian law requires that their claims for refugee protection should be considered here in Australia instead of expelling them to Malaysia," he told AFP.

At a special evening hearing in Melbourne, Justice Kenneth Hayne ordered that the group which was to leave Australia at 11.30am on Monday (9.30am Malaysian time) not depart before 4.15pm (2.15pm Malaysian time), pending a hearing in the High Court in Canberra at 2.15pm (12.15pm).

Outside court Manne said he did not know if this would set a precedent.

"We'll need to await the outcome of the court, but it has granted an interim injunction pending further argument - so they have put a stay on the deportation of the first 16 asylum seekers under the Malaysia solution," he said.

"Time will tell and we will need to look at the outcome of these proceedings."

Malaysia not signatory to UN convention on refugees

Ahead of the hearing, the government said it was prepared for protests and legal challenges and vowed the deal would go ahead despite concerns among rights campaigners that Malaysia has not signed up to the UN convention on refugees.

"We are determined to implement this," Immigration Minister Chris Bowen told Channel Ten.

"People who come to Australia by boat can work on the basis that they will be returned to Malaysia, regardless of any protest activity."

Two boats carrying a total of more than 100 suspected asylum seekers, including children, have arrived in Australia since the deal was signed, with the latest vessel detected on Sunday.

The immigration department confirmed that some from the first boat, which arrived at Australia's remote Indian Ocean detention centre on Christmas Island two days ago, were rejecting meals.

"A small number of the group that arrived on Friday have now missed consecutive meals," a spokeswoman told AFP.

Bowen said the new arrangement was designed to eradicate people-smuggling networks, and already appeared to have led to a fall in asylum seekers coming to Australia.

But the opposition said the change would not hamper people-smuggling.

"Boats have been continually arriving at a rate of one per week since the Malaysian people-swap agreement was announced (in early May)," spokesman Scott Morrison said, adding that almost 700 boatpeople had landed since then.

Asylum seekers arriving by boat to Australia peaked at close to 7,000 in 2010, but closer to 2,000 boatpeople have arrived this year.

- AFP