The Rudd government will begin processing the refugee claims of more than 22,000 asylum seekers who arrived by boat since the resumption of offshore processing last year.

Nearly a year after the introduction of the tough ''no advantage'' principle aimed at deterring boat arrivals, the first tranche of asylum seekers have been assigned migration agents and told they can begin applying for refugee status, Fairfax Media understands.

What he said was a total nonsense. A total fantasy. 

The move comes after Foreign Minister Bob Carr was criticised for suggesting that many recent boat arrivals were ''economic migrants'' rather than refugees. Human rights advocates said the government could not possibly know this because none had had their claims processed.

Now that processing is to begin.

A source said the first tranche of arrivals since August 13 last year - when offshore processing at Nauru and Manus Island was resumed and the ''no advantage'' principle put in place - have been told they can now apply for asylum.

But even if successful, they will still wait several years for their visas, sources told Fairfax Media.

Under the ''no advantage'' principle, asylum seekers who come by boat have to wait as long for resettlement as they would if they had stayed overseas in a refugee camp and waited for their claims to be processed through formal channels. It is not clear whether they will be able to work while waiting for their visas.

The new Immigration Minister, Tony Burke, is under pressure to grant such people work rights, especially those whose refugee claims are successful.

Senator Carr cut short a radio interview on Wednesday when he was pressed to justify his claim that up to 100 per cent of asylum seekers arriving on some boats were economic migrants seeking a better life rather than people fleeing persecution. He told Melbourne radio station 3AW that there was a ''changing profile'' among recent arrivals.

''In recent times … and I'm not prejudging individual claims … the profile of the current arrivals - Iranians, Sri Lankans and Vietnamese - has shifted,'' he said.

When quizzed how he knew this when more than 20,000 claims had not been assessed, he said he stood by his previous statements and hung up abruptly.

Also on Wednesday, former Liberal prime minister Malcolm Fraser branded Senator Carr's claims a ''total nonsense''. Mr Fraser, who has been a vocal critic of the asylum seeker policies of both major parties, said Senator Carr had no evidence for his claim.

''I think a lot of people [who] might have felt maybe some relief that Kevin Rudd was back in charge will now have that very heavily tempered by Senator Carr's most intemperate remarks,'' Mr Fraser said.

''What evidence does he have for this? What he said was a total nonsense. A total fantasy.''