Boris Johnson is self-isolating after meeting an MP who later tested positive for Covid-19, APA reports citing BBC.
The prime minister said he was contacted by NHS Test and Trace on Sunday but is not showing symptoms.
Mr Johnson on Thursday spent about 35 minutes with Ashfield MP Lee Anderson who has since tested positive.
The news came as No 10 said Mr Johnson would make "critical announcements" about coronavirus and "levelling up" the UK over the coming weeks.
In an announcement planned before Mr Johnson was told to self-isolate, Downing Street said there would be a "clear signal" of his "ongoing ambitions for the United Kingdom".
It said Mr Johnson would chair "key Covid meetings" and work with Chancellor Rishi Sunak to devise the upcoming spending review with an aim to fulfil his promise to "build back better".