Monday's transfer of a first group of asylum seekers from Australia to Malaysia has been delayed to allow a court to consider a last-minute challenge to the refugee swap.

A High Court judge in Melbourne ruled late Sunday that the transfer cannot go forward before late afternoon. That will permit another judge in Canberra to hear the challenge from a group called the Refugee and Immigration Legal Center.

Australia had planned to fly 16 men to Malaysia Monday morning. It would be the first transfer under a deal that will eventually see 800 undocumented asylum seekers taken to Malaysia for detention while their applications are processed. In return, Australia will accept 4,000 refugees from Malaysia who have already been approved.

The 16 men are among a group of 54 asylum-seekers whose boat was intercepted last month. Australia is still assessing the cases of some of the refugees, particularly those of a number of unaccompanied children.

Human rights groups and U.N. agencies have protested the swap, saying Malaysia has not signed international conventions on torture and the treatment of refugees. Australia over the weekend released photos of a former resort where the asylum seekers will initially be housed.

Australian authorities meanwhile have intercepted another boat filled with about 50 asylum seekers. Officials said that group will be taken to Christmas Island where they will be held until they can be transferred to Malaysia.

Thousands of refugees have tried to make their way to Australia from war-torn countries such as Afghanistan and Sri Lanka, often paying smugglers to take them across the seas in rickety boats. Australia says it is trying to discourage the practice because of the risk to the refugees.