Suella Braverman
In a letter to MPs she suggests there is a more than 50% chance the plan is incompatible with human rights laws.
The former Labour home secretary said it would turn the UK into a "pariah amongst western European states".
Rishi Sunak wants to "get a grip" on illegal migrants – but his plan is already under the microscope.
"Just like their botched Rwanda asylum scheme, this is immoral, ineffective and incredibly costly for taxpayers."
Home secretary says frustration with accommodation for asylum seekers is "understandable" amid demonstrations erupting into violence.
The Tory MP used a podcast to tell the prime minister where he was going wrong in his bid to reach a new Northern Ireland Brexit deal.
Labour's shadow minister for domestic violence accused the home secretary of being "missing in action".
Yvette Cooper said it was further evidence of "appalling failures" in the police.
A Holocaust survivor told the home secretary the same language had been used "to dehumanise and justify the murder of my family and millions of others".
"I am reminded of the language used to dehumanise and justify the murder of my family and millions of others".