A radio show hosted by shadow foreign secretary David Lammy on LBC is being investigated by Ofcom following complaints.

The media watchdog said it was looking into whether the programme on March 29 “broke our rules on politicians acting as news presenters”.

Mr Lammy announced Sir Jeffrey Donaldson’s resignation as DUP leader live on air.

Ofcom’s rules on due impartiality state: “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.”

The episode of the show garnered 53 complaints, Ofcom said on Monday.

Mr Lammy has hosted a show on the radio station since 2022 following appearances standing in for other presenters.

Last month, episodes of GB News programmes presented by Tory MPs were found to have broken broadcasting rules by them acting as newsreaders.

Ofcom’s probe involved shows that were presented by former House of Commons leader Sir Jacob Rees-Mogg, as well as Minister Without Portfolio Esther McVey and backbencher Philip Davies, and the channel was warned about potential sanctions if there are further breaches.

Married couple Ms McVey and Mr Davies are no longer part of the GB News line-up.

Also on Monday, Ofcom warned TalkTV following Julia Hartley-Brewer’s heated exchange about the Hamas-Israel war with Palestinian politician Dr Mustafa Barghouti on her show but declined to launch an investigation.

Ofcom said Ms Hartley-Brewer’s remarks “had the potential to be highly offensive to viewers” but due to their “brevity” and “audience expectations of this presenter and programme, which often features provocative viewpoints” did not reach the threshold for a probe.

“While TalkTV’s position is that Ms Hartley-Brewer’s comments were not motivated by Dr Barghouti’s religion or ethnicity, we recognise that many complainants understood them to be so. Given this, the comments had the potential to be highly offensive to viewers, irrespective of the intent of the presenter,” it added.

“We are therefore issuing strong guidance to TalkTV on the need to take greater care to ensure that potentially highly offensive comments are justified by the context in order to comply with the Broadcasting Code. We expect the broadcaster to take this guidance into account in future programming.”

The episode received more than 17,000 complaints.