Matt Hancock, the health secretary, has tested positive for coronavirus and is self-isolating at home.
The announcement came shortly after Boris Johnson also confirmed he had contracted the virus.
Hancock, 41, said the symptoms he has experienced so far had been “very mild and he as been able to “carry on with the work driven forward the UK response” to the pandemic.
He also said a “massive thank you to everybody in the NHS, working in social care and right across the board on the response”.
“I’ll be continuing to do everything I can to get our carers the support that they need. And I’ll be doing that from here but with no less gusto,” he said.
“And then from next Thursday, once I’m out of self-isolation and I hope with no more symptoms, then I’ll be able to get back stuck in and into the office where necessary.”
The first MP to be confirmed to have contracted coronavirus was health minister Nadine Dorries, who has now recovered.
Johnson, 55, is self-isolating in Downing Street after experiencing mild symptoms on Thursday.
The prime minister said he had developed a temperature and a persistent cough.
Johnson is the first world leader to have confirmed to have contracted the virus.
In a video message, the PM said: ”“Thank you to everybody who is doing what I’m doing, working from home to stop the spread of the virus from household to household.”
Downing Street refused to comment on Johnson’s pregnant fiancé Carrie Symonds.
Johnson got his results of the test at midnight last night and is now remaining in No.11 Downing Street, which is now serving entirely as the prime minister’s office and home. Johnson lives above the office in his flat.
All No.10 staff have been told to observe Public Health England (PHE) guidelines and will remain two metres apart from the PM at all times in the event they were to have contact.
Staff making meals for Johnson will knock on his door and leave the food outside before safely departing.
The latest figures from the Department of Health, released on Thursday, showed a total of 578 people who tested positive for coronavirus in the UK have died.
Johnson’s positive test was announced as police began fining people breaching coronavirus lockdown rules, less than 24 hours after new laws were brought into force