The lawyer for an Iranian family being held in a Texas detention centre for illegal immigrants says he hopes his clients will be back in Canada by Wednesday after receiving temporary passage.

"We're certainly hoping it's not going to be more than another 24 hours but at this point its really between the Canadian and American governments to make the arrangements for their travel," Andrew Brouwer told Canada AM on Tuesday.

Nine-year-old Kevin Yourdkhani (a Canadian citizen) and his parents were detained last month by U.S. Customs officials after their flight to Toronto made an unscheduled stop on American soil.

Customs officials say it was while they were checking passengers' documentation that they found a family with passports that had been reported stolen by the Greek government.

On Tuesday, Immigration and Citizenship Minister Diane Finley announced that the family would be granted temporary passage to Canada.

"The minister's decision was made in the best interests of the child,'' said Mike Fraser, a spokesperson for Finley.

Citing privacy concerns, Fraser said he couldn't comment on how soon the family may leave the T. Don Hutto facility outside Austin, Tex., or how long the family will be able to stay in Canada.

"All I can say is that we're in negotiations with U.S. authorities,'' he said.

The boy's Iranian parents fled to Canada in January 1995 and lived in Toronto for 10 years while seeking political asylum. Their son was born in Toronto in 1997.

They were denied refuge and were deported back to Iran in December 2005 after exhausting all their legal avenues.

"Unfortunately, under Canadian law, you can only make one refugee claim in your life -- notwithstanding what might have changed, what additional or new dangers you might be in," said Brouwer.

"So they don't have access to a proper oral hearing for a refugee claim, all they have is what's called a pre-removal risk assessment... that's their chance to explain that if they get sent back to Iran they'll be persecuted or tortured."

Inhumane conditions

The Texas facility -- formerly a maximum-security prison -- is the target of a lawsuit by the American Civil Liberties Union (ACLU), which is demanding U.S. officials release the family from the "inhumane conditions" and that the government be prohibited from separating Kevin from his parents.

Brouwer said Kevin is confined to a cell for most of his day.

"He sleeps on a steel cot right next to an open toilet, there's a little sink in a room and a door that's supposed to be closed for 11 to 12 hours a day," he said.

Officials with the U.S. Immigration and Customs Enforcement have rejected such accusations, saying the centre was opened to keep families together.

Kevin had written a letter to Prime Minister Stephen Harper, pleading for his family's release.

"I don't like to stay in this jail. Please bring me and my family to Canada," he wrote.

Kevin's mother, Masomeh Alibegi, said the boy lost four pounds in 10 days and has been sick with asthma but has been unable to get all the medication he needs. His father, Majid Yourdkhani, sleeps on a separate floor.

With a report from the Canadian Press