The controversial vessel - docked in Portland, Dorset - saw its first residents board earlier this month. But within days, the men were moved off after a Legionella outbreak was detected in the water supply.

It is not yet clear when asylum seekers will return to the barge, with Rishi Sunak's official spokesperson refusing to put a timetable on it.

But the government's plan is now facing a new challenge with a battle in the courts.

Mayor of Portland and local councillor Carralyn Parkes "put the government on notice" that she intended to launch a legal challenge against Home Secretary Suella Braverman on 7 August - though she said she was acting in a "personal capacity as a private individual and local resident" rather than as a politician.

Writing on her crowdfunding website for the action, Ms Parkes said: "If you or I want to put up a porch at our home, we need to apply for planning permission. It's wrong that the Home Office does what it likes without complying with the same rules.

"If they'd applied for planning permission, they would have had to consult with local people - but we never got the right to have our say. I also believe that planning permission would have been refused."

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Ms Parkes lawyers, Deighton Pierce Glynn Solicitors, also claimed the Home Office had not got a marine licence for the vessel needed for some coastal developments, demanding the Marine Management Organisation (MMO) issued an enforcement notice against the barge until such a licence had been obtained.

And they attacked Dorset Council for "continuing to maintain that it has no power to enforce planning rules over the barge".

Ms Braverman's response to the legal action had been due on Monday, but the department told them it would now not arrive until late next week.

A statement from Ms Parkes lawyers said: "We urge the Home Office and Dorset Council to respond to our client's letters and confirm their position and reasoning for their decision-making.

"Transparency is a key tenet of good governance. Those affected by authorities' decision-making are entitled to know what decisions are being made and why."

A Home Office spokesperson said: "It would be inappropriate to comment on ongoing legal proceedings."