British MP Nadine Dorries, a minister in the health department, has confirmed she has tested positive for coronavirus.
In a statement, Ms Dorries said she has self-isolated at home since finding out.
"Public Health England has started detailed contact tracing and the department and my parliamentary office are closely following their advice," she said.
Secretary of State for Health and Social Welfare Matt Hancock said he was sorry to hear about the diagnosis.
"She has done the right thing by self-isolating at home, and both NHS and PHE staff have been brilliant," Mr Hancock tweeted.
"I understand why people are worried about this disease. We will do all we can to keep people safe, based on the best possible science."
Ms Dorries, who helped craft the legislation to fight the virus, is the first British politician to be diagnosed with COVID-19, raising immediate concern about whether she has spread the infection.
The Times reported that she had been in touch with hundreds of people, including Prime Minister Boris Johnson.
She fell unwell on Friday while signing the document that declared coronavirus a notifiable disease, meaning companies could obtain insurance cover, said the paper, adding she was now believed to be on the road to recovery.
Ms Dorries has been Parliamentary Under Secretary of State at the Department of Health and Social Care since July 2019.
Six people have died in Britain from the virus, with 373 confirmed cases.
With AFP.