Plans to house 500 asylum seekers in a giant vessel in Portland, Dorset, are to be announced by the government today, Sky News understands.

The Home Office has been “exploring” the idea of using vessels to house asylum seekers to reduce the £6m daily bill of using hotels.

The government is expected to confirm today that the 93-metre long Bibby Stockholm “floatel” in Portland, Dorset, will be used to accommodate about 500 people.

The local Tory MP for the area, Richard Drax, has already threatened legal action over the floatel ,sparking fears in the Conservative Party of a fresh civil war.

Mr Drax, who has previously backed rigorous measures to cut the UK’s level of immigration, said the barge was “dumped on our door” without consultation by the Home Office and urged Home Secretary Suella Braverman to scrap the idea.

He told Sky News “lawyers are looking at it” and added the local police have also voiced their concerns about the plans.

“We want to get this consigned to the dustbin before anything’s signed,” he said.

The MP said the site is a “very, very restricted area” and raised concerns about keeping hundreds of vulnerable people there, which he said would place pressure on the port’s “very small” police force.

He said they would be bussed in from the port to nearby Portland Harbour, which is a “summer resort dependent almost entirely on visitors and tourists” with a crowded beach in the summer.

“With 500 migrants or more dumped here, I cannot see this is a sensible move, so for those reasons and many others I reject it,” he said.

“When they’re dropped off, and how many are? Where are they dropped off, what do they do, where do they go, do they come back?

“We already know some migrants have disappeared from hotels, we fear some into gangs. Are they going to stay here? No, there’s Bournemouth, Christchurch, Poole, Dorchester, Bridport to the west.

“They might just disappear into thin air so for all these reasons I’m not happy with it.”

The Tory-run Dorset council is also opposed to the use of Portland Port as the site of the vessel, which is effectively a large block of flats on a floating platform.

It could accommodate 506 migrants in 222 bedrooms on the three-storey vessel, at a reported cost of £20,000 a day.

The Times previously reported that the vessel would cost £15,000 a day to charter, while the cost of berthing it in Portland would be more than £4,500 a day. Additional costs would be required for services, including security and catering.