Donald Trump is facing criticism for retweeting the name of the alleged whistleblower whose complaint triggered the impeachment investigation into his dealings with Ukraine.

The US president, who has 68 million followers on Twitter, escalated his row with the Democrats by sharing a post from one of his supporters purporting to disclose the whistleblower’s identity, including his son Donald.

Until now Mr Trump had refrained from tweeting information about the individual, whose name has been shared on social media by the president’s conservative allies.

However, on Thursday he retweeted a post from his campaign “war room” which contained a link to an article in the conservative Washington Examiner with the alleged whistleblower’s name in the headline.