An “external person” may have been able to access the link to the Office for Budget Responsibility (OBR)’s fiscal outlook which was leaked before the Budget, the head of the watchdog has said.
An investigation has been announced after a document containing details of Rachel Reeves’ Budget was accidentally published shortly before midday on Wednesday, less than an hour before the Chancellor was set to announce the measures.
The report included growth forecasts, the extent of tax rises and the decision to lift the two-child benefit cap. It’s usually released after a chancellor has delivered their Budget statement to the Commons. Ms Reeves affirmed that this “must never happen again” but that she remained confident in Richard Hughes, the OBR chairman.
Mr Hughes told BBC Radio 4’s Today programme on Thursday morning that the leak appeared to come from outside the organisation.
“Well, the documents weren’t published on our webpage itself,” he said. “It appears there was a link that someone was able to access – an external person.”
The OBR previously said a “technical error” within the organisation was to blame for the early release and apologised.
Mr Hughes continued: “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,” he added. “We’re going to do that work quickly so people can have assurance in our systems and that can be restored.”
The investigation is set to involve expert insight from Professor Ciaran Martin, the former head of the National Cyber Security Centre, and will report to the Treasury and the Treasury Committee.
The chancellor told Sky News on Thursday: “Richard Hughes wrote to me yesterday evening, apologising for their error. It was a serious error, a serious breach.
“They have announced an investigation which will report to me very quickly.
“But I do have confidence in Richard and the OBR. They do important work. But what happened yesterday, it did let me down, and it shouldn’t have happened, and it must never happen again.”
Ms Reeves previously said she had found out about the early release while she was in the House of Commons preparing to deliver the Budget.
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,” he added. “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.”
