In a move that will shock absolutely no one who has ever read a government budget, the UK Statistics Authority has confirmed that Sir Keir Starmer, the Wales Office, and the Ministry of Defence (MoD) were all peddling some rather creative arithmetic about defence spending.

Back in March, the then-Prime Minister told MPs that ministers were boosting defence spending by a whopping £270bn. The Wales Office and the MoD later echoed this claim in June, presumably hoping no one would notice the fine print. But the UK Statistics Authority, the fun police of official figures, has now ruled that this is wrong. The £270bn is actually the proposed total defence spending for the 2025-26 to 2028-29 Parliament, not an increase. The Wales Office has since deleted a post on X that contained the dubious claim, likely with the digital equivalent of a red face.

A UK government spokesperson, in a masterclass of understatement, said: "We have previously acknowledged this phrasing and took immediate steps to ensure it was not replicated." Downing Street and Sir Keir's office, meanwhile, had nothing to add - perhaps because they were busy packing boxes, as Sir Keir resigned in July and was succeeded by Andy Burnham.

The saga began in March when Sir Keir told the House of Commons liaison committee: "We have already committed to 2.5% in 2027, and we will hit that. That means that, in this Parliament, we will spend £270bn more on defence than we would otherwise have done." The MoD and Wales Office repeated similar lines in June, with the latter tweeting on 3 June: "The UK government is increasing defence spending by £270bn over this Parliament to strengthen our national security."

BBC Wales learned that the figure originated in the MoD, not the Wales Office, which was then led by Welsh Secretary Jo Stevens. The Wales Office, a UK government department that oversees devolution and advocates for Wales in Westminster, apparently took the MoD's word at face value - a rookie mistake.

In a letter to Tory shadow defence secretary James Cartlidge, UK Statistics Authority interim chair Penny Young laid down the law: "We agree that it is incorrect and misleading to describe the £270bn as an increase in defence spending over the course of this Parliament, or to describe it as an extra £270bn. The £270bn represents the proposed overall spending on defence over the lifetime of the current Parliament, from 2025-26 to 2028-29."

The Wales Office told the authority the figure "was a mistake and was amended as soon as it was noticed," and has since reviewed its press office lines and quality assurance processes to avoid repeating the error. The MoD, for its part, has pledged to use "precise and consistent language" in future - a novel concept for government communications.

Conservative Shadow Wales Secretary Mims Davies MP, never one to miss a chance to tut, said: "At a time of growing global instability, the public deserves honesty and transparency about our defence budget. Labour ministers and civil servants in the Wales Office should be setting out the facts, not presenting figures in a way that risks misleading people."

Indeed, because if there's one thing the public needs in times of crisis, it's accurate budget figures - not inflated ones that make the government look like it's spending more than it actually is. But hey, at least the Wales Office has learned its lesson. Until next time, when they'll probably mix up billions and millions again.