The White House has said it is investigating how plans for airstrikes in Yemen were accidentally leaked in a messaging group that included a journalist – a move demanded by leading Democratic politicians.

The Atlantic magazine’s editor Jeffrey Goldberg said he was unexpectedly added to the chat - which included discussions of action against Houthi rebels.

The chat included US Defence Secretary Pete Hegseth and Security Advisor Mike Waltz.

Mr Hegseth is said to have posted operational details - but he has denied anyone was texting war plans.

“You're talking about a deceitful and highly discredited so-called journalist who's made a profession of peddling hoaxes time and time again,” he said.

Leading Democrat politician Pete Buttigieg said this leak is beyond belief.

“To see this administration claiming that it cares about competence and merit and then be responsible for an epic [mess] up like this demonstrates that these are not serious people,” he said.

Other leading Democrats in the US have said they are "not surprised" the Trump administration was unaware a journalist was in their group chat.

Jeffrey Goldberg told NBC he was in shock when he was accidentally added to the group chat.

“I assumed that I was being spoofed or hoaxed or being included in some kind of disinformation campaign, because it was simply too improbable to me that they would have such poor operational security,” he said.

U.S President Donald Trump. Credit: Daniel Torok/White House Photo/Alamy Live News. 13th Mar, 2025.

On Newstalk Breakfast, University of Galway law lecturer and political columnist with The Journal, Larry Donnelly, said this is “a colossal screw up”.

“The first thing I'd say is, you know, signal is an app that most of us have on our phones, or a lot of us have on our phones - the fact that it is being used to conduct national security policy, to me, is absolutely extraordinary,” he said.

“I mean, signal is an encrypted app, but at any rate, you would think that they would have their own specific system for communications like this.

“How Goldberg, the editor of The Atlantic, got added to this really defies any logic or anything I can come up with.

“The question becomes is the person who made a career over firing people actually going to fire his National Security Advisor, Mike Waltz? My guess is no.”

Mike Waltz. 04/11/2023 (AP Photo/Phelan M. Ebenhack)

Mr Donnelly said that while the leading Democratic politicians have demanded an investigation into the leak, he doesn’t think one is needed.

“I'm not sure how much of an investigation is needed here - the goods are all out there in the open, we know exactly what happened,” he said.

“Waltz added Jeff Goldberg to this conversation, nothing more needs to be discussed.

“To me, that is an error of such a colossal scale that I think he needs to go - I just don't see there’s any defending on this front.

“But again, we know Donald Trump operates quite differently.”

US Vice President JD Vance greeting Micheal Martin at a breakfast meeting he hosted at his official residence in Washington DC for the visit by the Taoiseach. Picture date: Wednesday March 12, 2025. Image: Alamy

Mr Donnelly said the hatred for Europe seen in these messages is scary.

“The biggest story here, in my view, for the rest of the world, is the absolute contempt that these messages reveal in the highest echelons of Government for Europe,” he said.

“We have JD Vance saying, ‘I just hate bailing Europe out again’ and Pete Hegseth then says, ‘I fully share your loathing of European free loading, it's pathetic’ with pathetic on capital letters.

“That is very, very worrying from a European point of view and it certainly belies the goodwill and everything that we saw from JD Vance on March 12th.”

Mr Donnelly thinks US President Donald Trump will ride out this controversy.

Split image of Jeffrey Goldberg, the editor of The Atlantic (L) and the White House (R).