OBR chief offers to resign over Budget leak chaos

The document, which revealed the contents of Rachel Reeves’ Budget, was accidentally published shortly before midday on Wednesday, half an hour before the Chancellor announced the measures.

The head of the OBR Richard Hughes confirmed he would quit if the Chancellor and the Commons committee lost confidence in him over the incident.

He said: “We take budget security incredibly seriously, which is why this investigation is already under way and will report very swiftly by early next week.

“Personally, I serve day-to-day subject to the confidence of the Chancellor and the Treasury Committee. If they both conclude, in light of that investigation, they no longer have confidence in me then, of course, I will resign, which is what you do when you’re the chair of something called the Office for Budget Responsibility.”

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In an interview on Thursday morning, Mr Hughes said an “external person” may have been able to access the link to the fiscal outlook

He said: “Well, the documents weren’t published on our webpage itself.

“It appears there was a link that someone was able to access – an external person.

“We need to get to the bottom of what exactly happened. We’re going to do a full investigation.

“There’ll be a full report to Parliament.

“We’re going to do that work quickly so people can have assurance in our systems and that can be restored.”

Mr Hughes said the investigation would include expert insight from Professor Ciaran Martin, the former head of the National Cyber Security Centre, and would report to the Treasury and the Treasury Committee.

On Thursday, Ms Reeves said she retains confidence in Mr Hughes despite the leak, but admitted she was "at the higher end of the anger scale" when she discovered her Budget had been leaked.

Speaking to Nick Ferrari on LBC on Thursday, the shadow chancellor said the OBR “needs reform” but felt it was “generally” fit for purpose.

Sir Mel Stride said: “Clearly, this latest incident is both unprecedented and deeply worrying that they should have, for whatever reason, have leaked or posted up the entire contents of their report before the Chancellor had actually stood up in the House of Commons.

“But I think generally, the OBR is important because it’s an independent body.

“It does mark the Chancellor’s homework, it does tell us whether she’s on target or not to meet her fiscal rules and I think it’s better that an independent body does that than the Chancellor does that herself.”