Treasury Launches Investigation into Possible Leak of Autumn Budget Details

The UK Treasury has launched an investigation into how details of a temporary increase in bank tax appeared in the media hours before the Chancellor delivered the Autumn Budget.

 The investigation was confirmed on Tuesday 10 November after the department's most senior civil servant, permanent secretary James Bowler, wrote to the Treasury Committee.

The report concerned a temporary increase to a levy on banks, details of which were published by Bloomberg on the morning of the Budget on 28 October. The report said the increase would be lower than lenders had feared, prompting a rise in bank shares before the Chancellor's announcement.

In his letter to MPs, Bowler said he had been assured that banks, their representatives and trade bodies had not been briefed on the changes before the Budget statement. However, he acknowledged that there had been a necessary widening of the number of people within government who knew the details shortly before the announcement.

The investigation is intended to establish how the information reached the media and whether confidential Budget information was improperly disclosed. Treasury Committee chair Meg Hillier said she expected investigators might find no evidence of a breach, but criticised previous inquiries that had failed to identify those responsible for leaks.

Hillier said she would seek further answers when the Chancellor appeared before the committee on Wednesday. The latest inquiry adds to pressure on the Treasury to strengthen the security surrounding major fiscal announcements. It follows previous incidents in which information connected to economic policy became public before official announcements.

Those earlier inquiries did not identify the source of the disclosures. The timing of Budget information can matter to financial markets because investors may react to changes in tax policy before the measures are formally announced.

The Treasury has not publicly identified a person responsible for the latest disclosure, and the investigation remains ongoing.

The committee is expected to examine the department's handling of confidential information and the safeguards in place ahead of major economic announcements.