Ofcom has launched an investigation into whether GB News breached impartiality rules by airing an interview between two Tory MPs and Chancellor Jeremy Hunt.
Esther McVey and Philip Davies spoke to Mr Hunt on March 11 ahead of the spring Budget, prompting criticism from some.
Media watchdog Ofcom said it was looking at whether the show broke its rules “requiring news and current affairs to be presented with due impartiality”.
SNP MP John Nicolson, who sits on the Digital, Culture, Media and Sport Committee, previously suggested there had been a breach because the pair acted as interviewers.
Ofcom chief executive Dame Melanie Dawes later wrote to the committee to clarify the rules on politicians presenting and appearing on TV programmes.
The guidelines currently say: “No politician may be used as a newsreader, interviewer or reporter in any news programmes unless, exceptionally, it is editorially justified.
“In that case, the political allegiance of that person must be made clear to the audience.”
A number of serving MPs currently host programmes on TV.
Former culture secretary Ms Dorries hosts a Friday night talk show for TalkTV, while Tory MP for North East Somerset Rees-Mogg is fronting a regular programme for GB News.
The watchdog said it had “exceptionally” decided to publish the reasons for its decision because its assessment had involved “matters of public interest”.
A spokeswoman said: “In our view, the combination of pre-recorded interview, in-depth studio analysis and panel discussion within this long-form programme was consistent with a current affairs format.
“At the time of broadcast, Ms Dorries was not standing in an election taking place, or about to take place.
“A range of alternative viewpoints, providing challenge and context to those of Mr Johnson, his Government and the Conservative Party more generally, were reflected in the studio panel discussions which were interspersed between each segment of the interview with the former Prime Minister.
“Given this, the programme did not raise issues under our rules preventing politicians from presenting news programmes, or those concerning due impartiality.”
Ms Dorries has since she will stand down as MP for Mid Bedfordshire at the next general election.
In March, shadow culture secretary Lucy Powell said the employment of serving MPs as presenters was “very concerning”, adding that Ofcom “should be looking at these issues”.
The same month Ofcom ruled an episode of GB News’ Mark Steyn show, who was a presenter until earlier this year, broke its broadcasting rules and was “potentially harmful and materially misleading”.
Mr Steyn made an “incorrect claim” about health data providing evidence of a link between the Covid vaccine and higher rates of infection, hospital admission and death, Ofcom said.
GB News has been approached for comment.