Labor frontbencher Kristina Keneally will fly commercially to visit a Tamil family detained on Christmas Island after accusing Peter Dutton of cancelling her trip.
The Murugappan family was removed from their home in the central Queensland town of Biloela three years ago, sparking a major campaign for their release.
Senator Keneally had been due to visit them while on a parliamentary committee trip but received last-minute advice the RAAF plane that had been booked was unavailable.
She said Mr Dutton, who is the defence minister, cancelled the committee's special purpose aircraft after it emerged she would visit the family.
But on Thursday evening she will travel to Christmas Island on a Virgin flight.
"I am glad I will be able to meet many members of the Christmas Island community during my visit, and of course, I especially look forward to meeting Nades, Priya and their two Australian-born little girls," Senator Keneally said.
During Senate estimates on Wednesday, the Australian Border Force confirmed the Labor senator had permission to attend the detention centre and wished her a pleasant visit.
"Within an hour of that information becoming public, Peter Dutton did the one thing he could as defence minister and cancelled the committee's flight on a government special purpose aircraft," she said.
A government spokesperson told the ABC all the planes were in use or undergoing maintenance.
"It is fundamentally wrong to suggest this was done to stop Kristina Keneally's visit," the spokesperson said.
"She has been approved to visit the (detention) centre and could fly commercially."
Senator Keneally said Prime Minister Scott Morrison and his ministers could use their discretion to bring the family home.
"They are simply choosing not to intervene, allowing this cruel and inhumane saga to continue at considerable cost - some $50 million - to the taxpayer," the opposition home affairs spokeswoman said.
The Biloela family of Priya, Nades and their Australian-born daughters Kopika and Tharunicaa have spent more than three years in detention.
Community members have campaigned for them to be returned to their adopted home.
Australian Associated Press