UK Prime Minister Boris Johnson will undertake "only essential government business" in the week ahead after the state health service designated him a close contact of a person infected with Covid, Downing Street said Sunday.

British Prime Minster Boris Johnson leaves 10 Downing Street for Prime Minister's Questions, in London, Britain on March 18, 2020. (Photo by Tim Ireland/Xinhua)

Johnson and finance minister Rishi Sunak were both designated but are taking part in a government pilot scheme that enables them to continue working, a spokesperson said, after Health Secretary Sajid Javid confirmed on Saturday he had tested positive for Covid-19.

Participating individuals must take daily tests and self-isolate when not at work, according to the pilot's rules. The development comes just as Johnson's government prepares to jettison most pandemic restrictions in England on Monday.