Jacob Rees-Mogg is under investigation from the media watchdog Ofcom over a breach of its editorial guidelines.
The regulator received 40 complaints after the former cabinet minister acted as a newsreader during his State Of The Nation show on May 9 as a civil trial verdict involving US president Donald Trump was announced.
Under the rules, politicians are prevented from taking a newsreader role unless it is “editorially justified”.
Rees-Mogg is just one of a number of Tory MPs with shows on GB News, joining Lee Anderson, Esther McVey and Philip Davies.
Ofcom said: “We received 40 complaints about this programme, presented by Jacob Rees-Mogg MP, which covered a breaking news story about a civil trial verdict involving former US President Donald Trump.
“Our investigation will look at the programme’s compliance with our rules which prevent politicians from acting as newsreaders in any news programmes, unless exceptionally, it is editorially justified.”
Rees-Mogg hosts the hour-long evening show from Mondays to Thursdays.
Ofcom recently launched a consultation into the rules around politicians presenting programmes, which were introduced in 2005.
“Given the rise in the number of current affairs programmes presented by sitting politicians and recent public interest in this issue, we are conducting new research to gauge current audience attitudes towards these programmes,” it said last month.