Downing Street has refused to say when the government will try to put asylum seekers back on the Bibby Stockholm.
All 39 people being housed on the barge in Dorset were removed on Friday after Legionella was discovered in the on-board water supply.
Asked when they would return, the prime minister’s spokesperson said on Monday: “We’re not putting a timeline on that.
“We do expect them to be back onto the boat as soon as possible.
“The Home Office is awaiting the results of further tests. Once those have been completed, obviously the intention is to return people.”
The government is under pressure to explain exactly when it knew the bacteria had been found.
No.10 has said Home Office ministers were told about it on Thursday night.
But Dorset Council has said it told the Home Office about the Legionella test results last Monday.
Ministers are also facing questions about why people were moved onto the barge even though the results of the tests had not yet come back.
Steve Barclay, the health secretary, told the BBC this morning “no-one has been harmed” by the outbreak.
The row came during what had been dubbed “small boats week”, a days-long media push by the Conservatives to show Rishi Sunak’s plan to crack down on migration was working.
But the media strategy was also overshadowed after six people died attempting to cross from France to the UK on Saturday when their boat sank, 59 people were rescued.