The first migrants have arrived on board the Bibby Stockholm barge.
The group arrived at the accommodation vessel moored in Portland Port, Dorset, on Monday with more people expected later in the day, the PA news agency understands.
It comes as Home Office minister Sarah Dines said the barge would be in use “imminently”, despite a series of delays.
Ms Dines also confirmed “all possibilities” for tackling the migrant crisis are being examined, following reports that the Government is considering reviving plans to fly people who arrive by unauthorised means 4,000 miles to Ascension Island.
While only a small number of migrants are expected to be housed on the barge at first, Ms Dines indicated it could increase rapidly to its capacity of around 500 men.
Pressed on whether all of them could be on board by the end of the week, Ms Dines told BBC Radio 4’s Today programme: “Yes, quite possibly it will be 500. We are hoping.”
But Downing Street appeared to suggest she had misspoken, with the Prime Minister’s official spokesman saying that while “no limit” had been set on how many people would board the barge this week, the Government’s plan was to reach the capacity “over time”, adding: “I don’t think we are aiming to do it by the weekend.”
The Home Office later clarified the total would be reached over a longer period of time and not by the end of the week.
Human rights campaigners Amnesty International UK condemned using the barge to house asylum seekers.
Steve Valdez-Symonds, the charity’s refugee and migrant rights director, said: “It seems there’s nothing this Government won’t do to make people seeking asylum feel unwelcome and unsafe in this country.
“Reminiscent of the prison hulks from the Victorian era, the Bibby Stockholm is an utterly shameful way to house people who’ve fled terror, conflict and persecution.
“Housing people on a floating barge is likely to be re-traumatising and there should be major concerns about confining each person to living quarters the typical size of a car parking space.”
The Government hopes the use of the barge and former military bases to house asylum seekers will reduce the cost of hotel bills.
Ms Dines said those arriving in the country via unauthorised means should have “basic but proper accommodation” and that they “can’t expect to stay in a four-star hotel”.
Meanwhile, other measures being considered to curb Channel crossings include the revival of previously-dropped plans to send asylum seekers to Ascension.
The proposals to use the British Overseas Territory are apparently being considered by ministers and officials as a “Plan B” if the Rwanda scheme fails.
The volcanic island in the South Atlantic could house an asylum processing centre.
The plans to remove asylum seekers who arrive by unauthorised means to Rwanda have been stalled by legal challenges that will end up in the Supreme Court.
Asked why the Ascension Island plan is being reconsidered after seemingly being rejected by Boris Johnson’s government, Ms Dines said “times change”.
Speaking to Sky News, the safeguarding minister said: “We look at all possibilities. This crisis in the Channel is urgent – we need to look at all possibilities and that is what we are doing.
“We are determined to make sure there isn’t the pull factor for illegal migrants to come to this country, basically to be abused by criminal organised gangs.
“These are international operations and they have got to stop.”
The Prime Minister’s official spokesman would not comment on “speculation” over Ascension Island but PA understands the Government is not actively pursuing the proposal.
The developments came during the Government’s “small boats week”, in which it is making a series of announcements on the issue that Prime Minister Rishi Sunak has promised to solve.
Fines for employers and landlords who allow people who arrive by irregular means to work for them or live in their properties are to be hugely increased.
Civil penalties for employers will be increased up to a maximum of £45,000 per worker for a first breach and £60,000 for repeat offenders, tripling both from the last increase in 2014.
Landlords face fines going from £1,000 per occupier to £10,000, with repeat breaches going from £3,000 to £20,000. Penalties relating to lodgers will also be increased.
More than 15,000 migrants have arrived in the UK so far this year after crossing the Channel, Government figures show.
Some 339 people made the journey on Friday and Saturday after an eight-day hiatus amid poor weather conditions at sea, taking the provisional total for 2023 to date to 15,071.
According to the Home Office, no crossings were recorded on Sunday.
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