One of Britain’s most senior rabbis has joined religious leaders of other faiths in calling for Home Secretary Amber Rudd to limit the time immigrants spend in detention to 28 days.

Reform Rabbi Laura Janner-Klausner urged the government to act to limit immigration detention in post-Brexit law, noting that the UK is only European country to hold people with no judge’s oversight and no release date.

The Government’s use of indefinite detention was “unjust, ineffective and inhumane,” she said, in tandem with Christian, Muslim, Hindu and Sikh leaders.

“Evidence shows that indefinite detention causes huge harm, not only to those detained, but to their family, children, friends and community,” they wrote in an open letter, published on Friday. “The time to act is now.”

Every year, the Home Office holds around 30,000 people on immigration grounds, including elderly people and survivors of rape, torture and slavery, making it one of the largest detention regimes in Europe.

No judge signs off on immigrants’ detention and there is no legal limit on how long they can be held “purely for the administrative convenience of the Home Office”.

The UK’s use of indefinite detention has been criticised by the United Nations and Her Majesty’s Inspectorate of Prisons, as well as civil rights groups such as Liberty, which has called it “a black hole at the heart of British justice”.

Research by the British Medical Association has revealed that indefinite detention causes serious mental and physical harm, and Janner-Klausner said the policy went against Britain’s “proud record of treating people with decency and fairness”.

She said: “We deserve an immigration and asylum policy that is humane and sensible. Locking up nearly 30,000 men, women and children indefinitely every year is unjust and counterproductive. I urge the Home Secretary to place a time limit on immigration detention.”