British Prime Minister Boris Johnson was admitted to hospital for tests on Sunday after suffering persistent coronavirus symptoms 10 days after testing positive for the virus, though Downing Street said he remained in charge of the government.

Johnson, who was isolating in Downing Street after testing positive last month, still had a high temperature and so his doctors felt he should go to an undisclosed hospital for tests in what the government said was a “precautionary step”.

“On the advice of his doctor, the prime minister has tonight been admitted to hospital for tests,” his Downing Street office said in a statement. Johnson is expected to stay overnight.

“This is a precautionary step, as the prime minister continues to have persistent symptoms of coronavirus ten days after testing positive for the virus,” the statement added.

News of his hospitalisation came only after an hour after Queen Elizabeth delivered a rallying call to the British public saying they would overcome the coronavirus outbreak if they stayed resolute.