Legionella bacteria can cause a potentially deadly lung infection known as Legionnaires' disease. It is contracted by people breathing in droplets of water containing the bacteria.

None of the migrants on the barge have shown any symptoms of the disease, according to the Home Office.

Asylum seekers were removed from the barge on Friday after Legionella bacteria was found in the vessel's water system.

It later emerged that people spent four days on board the barge after the bacteria was discovered and before they were removed by the Home Office as a "precautionary measure" - prompting a blame game about what the government knew and when.

Dorset Council has said Home Office contractors were notified about the results last Monday - four days before people were moved off the barge.

The council went on to claim a Home Office staff member was informed about the bacteria on Tuesday.

However, a government source previously told Sky News there is no record of this conversation, and claimed the Home Office only received a written notification about the Legionella on Wednesday evening.

Speaking to Sky News, Mr Barclay said ministers were informed about traces of the bacteria only on Thursday.

Asked about claims the Home Office was informed about test results which discovered the bacteria on Tuesday, he said: "This is a standard thing the council had done. There is no reason to suggest there were concerns. As a precaution the tests were done.

"As soon as ministers were notified on Thursday night, there were some concerns with that, they took instant action."

He added: "It may be the council notified the Home Office, that is an issue for those in the Home Office to respond to, obviously this is a Home Office lead.

"My understanding from colleagues in the Home Office is it was notified to Home Office ministers on Thursday and they then took very quick action as a result."

And asked whether people should be put back on the Bibby Stockholm despite the controversy, Mr Barclay replied: "Yes, I do, because it's costing around £6m a day in terms of the cost of hotels.

"It's important that we both maintain safety standards, but also reflect the pressure on the taxpayer position in terms of that £6m."

The health secretary also said no migrants had shown signs of illness from Legionella.

"There has been no concerns in terms of anyone that has been on the barge and all those people are being subject to health assessments," he said.

The barge is one of a number of alternative sites the Home Office is using to end reliance on expensive hotels for asylum seekers, which the government says is costing the taxpayer £6m a day.

Its operation has been mired in controversy after its opening was delayed several times before it finally opened to asylum seekers last Monday.

Charities have warned that those on board the boat have been "re-traumatised" after they were evacuated following the discovery of Legionella.

Conservative ministers have faced calls to resign over the saga, with former cabinet minister David Davis saying the evacuation "revealed the startling incompetence of the Home Office itself".

"Rather famously many years ago, John Reid, when he took over as home secretary, talked about it being not fit for purpose, and I'm afraid you're seeing that here," he told BBC Radio 4's programme.

"It's really, really hard to understand how, at all layers, this could not be caught early."

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He added: "Even working properly, the Bibby barge would only take effectively one day's arrivals. So it's not a solution to the problem and all of this is going to go on until the Home Office is able to process these arrivals more quickly."

The government believes the existence of the barge will serve as a deterrent to those arriving in England via small boats in the Channel.

However, in a further blow to Rishi Sunak, last week saw the highest daily number of people cross the Channel, with 755 migrants making the journey on Thursday.

It brought the cumulative total since records began in 2018 to over 100,000.

The government was then forced to defend its immigration strategy after at least six people died after a small boat crossing from France to the UK capsized and sank, in what was described as an "appalling and preventable" tragedy.