Michael Gove is isolating after coming into contact with Australia’s deputy prime minister, who has tested positive for coronavirus.
The communities secretary is the third minister to confirm they are isolating after meeting with Barnaby Joyce, who was in the UK earlier this week.
Mr Joyce tested positive for COVID-19 while travelling to Washington DC and is awaiting results to see if he has the Omicron variant.
Although Mr Gove is not thought to have any symptoms at present, he is taking this precaution until a negative test result is confirmed.
A spokesman for Mr Gove said he met Mr Joyce on Monday.
Justice Secretary Dominic Raab and Transport Secretary Grant Shapps are also isolating.
Mr Shapps pulled out of a visit to Newton Aycliffe, County Durham on Thursday, where he was due to mark the signing of a major contract with Hitachi to manufacture rolling stock for HS2.
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The transport secretary tweeted: “Sorry not to be travelling to @HitachiRailENG in County Durham today to welcome huge new @HS2ltd rolling stock contract.
“Have taken precaution of cancelling visit & have taken PCR test after being in contact with Australian deputy PM this week – who’s tested positive for COVID.”
A spokeswoman for Mr Raab said: “He is getting tested and he is self-isolating while we wait to hear whether the Australian deputy prime minister has Omicron or not.”