Headed for Australia: The Tamil asylum seekers get on board an airplane at Cocos Island.

The asylum seekers pictured getting on board an aeroplane at Cocos Island, on their way to mainland Australia. Photo: AAP

The 157 asylum seekers brought to Western Australia are economic migrants, Immigration Minister Scott Morrison has claimed.

After spending weeks detained on the Customs ship Ocean Protector, the 157 people were transferred by plane to the Curtin detention centre on Sunday night. They will now have their identities checked by Indian officials.

Minister Morrison defended the government's intention to return the asylum seekers to India, telling ABC radio that if people could not be taken to India ''what is next? New Zealand?''

''These people have come from the safe country of India ... a passage here is nothing more than an economic migration seeking to illegally enter Australia,'' Minister Morrison told ABC radio.

''The suggestion that people who have left a safe country are somehow fleeing persecution, I think, is absurd.''

Mr Morrison called India a ''vibrant democracy'' that has received praise from the United Nations High Commissioner for Refugees for its support of Sri Lankan refugees. Most of the 157 are understood to be Tamils who fled Sri Lanka during, and after, the country's decades-long civil war.

The decision to transfer the asylum seekers to Australian soil pre-empts the outcome of a High Court challenge to their detention at sea.

A court hearing is scheduled for Monday afternoon.

For the four weeks they were held at sea, the asylum seekers were kept in windowless rooms for 21 hours a day with only three hours outside. Families were separated and they didn't have access to translators.

Mr Morrison did not say what would happen to the asylum seekers if they were not accepted by India. After talks with Australia, the Indian government has only committed to accepting the asylum seekers that are Indian citizens. They have agreed to consider the non-citizen Indian residents.

''It's a fundamental principle of refugee law that no one, no person, should be made to deal with the authority of the country from which they have fled," said the Refugee and Immigration Law Centre's David Manne.

Minister Morrison says that India's processing of these people is ''something for any government to do, who is the host government who is determining their citizenship or residency and it's not for Australia to do that''.

Greens leader Christine Milne criticised the government's actions, calling it ''wrong all round''.

''As far as Scott Morrison and the Prime Minister are concerned, it's all about chest beating and saying nobody can land in Australia rather than dealing with people appropriately,'' Senator Milne told reporters.

with Ben Doherty

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