Twitter has flagged a tweet written in March by a Chinese government spokesman that suggested the US military brought the novel coronavirus to China, as the social media platform ramps up fact-checking of posts.

Twitter posted a blue exclamation mark under a tweet by Chinese Foreign Ministry spokesman Zhao Lijian, with a comment urging readers to check the facts about Covid-19.

Clicking on the link directed readers to a page with the headline, “WHO says evidence suggests Covid-19 originated in animals and was not produced in a lab”.