Rishi Sunak’ and Liz Truss have clashed on immigration ahead of a TV debate which could go a long way to determining who becomes the next prime minister.
Both candidates unveiled their plans to toughen the UK’s borders if they win the race to succeed Boris Johnson.
Truss said she would seek to strike more Rwanda-style deportation deals with other countries, while doubling the number of Border Force officials to prevent migrants trying to cross the Channel from France in small boats.
Sunak proposed imposing a cap on the number of refugees the UK accepts, while also putting illegal immigrants on cruise ships moored around the country.
But allies of Truss said that would be illegal under the Human Rights Act and the European Convention on Human Rights.
One said: “It could amount to arbitrary detention and a breach of domestic and international law.
“Proposals must be deliverable and grounded in reality, not simply warm words. His plan has no detail on how he will get around international law or the UK courts.”
Sunak told the BBC that tackling illegal migration was a “priority” for him.
But he was unable to give a clear assurance that his policy proposals would be legal.
“What we do need to do is be very honest about the challenges that the ECHR, these European laws, have on our ability to grapple with this problem,” he said.
“I’ve said that no options should be off the table. We have a new British Bill of Rights that’s being introduced into Parliament that I believe will help solve the challenges.
“And I’ve put some other further points in the plan today saying how we could do things differently from the European Convention to strengthen our ability to deport people who shouldn’t be here and protect our borders.”
A spokesperson for Sunak said: “Rishi is clear he will do whatever is legally necessary to ensure adults who come to this country illegally have no route to asylum.”
The two leadership contenders will go head-to-head in a live debate on the BBC on Monday night, the first one since they made it to the final run-off.
The last time they met was in the ITV leadership debate, which was held before Penny Mordaunt, Kemi Badenoch and Tom Tugendhat were eliminated.
The pair clashed over the economy, as well as each other’s backgrounds, which led to them pulling out of a debate a planned Sky News debate because of the damage they were doing to the Tory party.