TV watchdog Ofcom has launched a probe into Sir Jacob Rees-Mogg's GB News show amid a flurry of complaints over an episode covering a court case involving Donald Trump.
The media regulator received 40 complaints objecting to the former Cabinet Minister acting as a newsreader during his State Of The Nation show on May 9.
Under the rules, politicians are prevented from pretending to be newsreaders unless it is "editorially justified".
The investigation will look at whether the GB News programme abided by these guidelines when it reported on a civil trial verdict reached that day on the former US president.
Sir Jacob reported an update from the case to the audience before turning to his guests, who included former Ukip leader Nigel Farage.
An Ofcom spokesman said: "We are investigating whether this programme broke our rules, which prevent politicians from acting as newsreaders, unless exceptionally, it is editorially justified."
Sir Jacob, who was handed a gong in Boris Johnson's resignation honours, has declared £90,600 in earnings from the show since it launched in February, according to the latest register of members' interests.
A string of top Tories host shows on GB News, including Deputy Chairman Lee Anderson.
Married Tory right-wingers Esther McVey and Philip Davies, who host a programme together, are also being investigated by Ofcom over a potential impartiality breach.
The two senior Conservatives interviewed Chancellor Jeremy Hunt on March 11 on the channel, ahead of the Budget.
Ofcom said it will also investigate an episode of Talk TV's Richard Tice presented by the leader of the Alba Party Alex Salmond on April 2.
Ofcom has said it received two complaints regarding the impartiality of the programme, specifically in relation to a discussion on whether the SNP was "holding back the course of independence".
