Britain's opposition Labour leader Keir Starmer says he is self-isolating after coming into contact with someone who has tested positive for Covid-19, the third time he has needed to quarantine.

“I have no symptoms and will be working from home until next Monday,” Starmer said on Twitter.

Starmer also had to self-isolate in September after a member of his household showed symptoms of the virus and again in December after a member of his staff tested positive.