Britain’s immigration minister Robert Jenrick resigned on Wednesday saying the government’s published draft emergency legislation aimed at getting its Rwandan migrant deportation scheme up and running did not go far enough.

Jenrick said in a resignation letter that the legislation offered one of the last opportunities to tackle the small boats crisis before an election expected next year and the government’s plans were a “triumph of hope over experience”.

The legislation needed to go further to limit the opportunities for domestic and international courts to challenge the policy, he said.

“The government has a responsibility to place our vital national interests above highly contested interpretations of international law,” he said in his resignation letter to Prime Minister Rishi Sunak, which he posted on X.

“I am unable to take the currently proposed legislation through the (House of) Commons as I do not believe it provides us with the best possible chance of success.”

Jenrick was a close political ally of Sunak. In 2019, the two wrote a joint article with Oliver Dowden, now the deputy prime minister, backing Boris Johnson for the Conservative Party leadership.

A member of parliament since 2014, Jenrick previously served as a junior minister in the health and finance departments as well as Secretary of State for Housing, Communities and Local Government.

Over recent days, Jenrick, who had been immigration minister since October last year, has been more outspoken on the need to tackle the arrival of small boats on the southern coast of England.

On Tuesday, Jenrick said that people who arrived in the small boats were breaking into Britain and it was “profoundly wrong” for people to be entering the country in this way.

“If you or I crossed an international border, or literally broke into another country, we would expect to be treated very seriously,” he told Sky News.