Moves to curb a “culture of excess” in public sector pay have been unveiled by Gordon Brown as part of a bid to slash £12bn from spending over the next four years.

The prime minister has ordered a review of senior pay, required ministerial approval for £150,000-plus salaries and threatened to “name and shame” the worst offenders.

He launched his assault as the government published details of where it hopes to find another £3bn of savings on top of those promised in the last Budget.

Swingeing cuts to spending on consultants and publicity, axing or merging 123 quangos and moving more staff out of London were all in the Smarter Government report.

Mr Brown also suggested money would be found by forcing people to access services online - saying millions more pounds would be put into securing UK-wide internet access.

And health secretary Andy Burnham confirmed £600m would be found by cancelling some elements of the NHS IT programme.

The stark messages came ahead of Wednesday’s pre-Budget report, in which Chancellor Alistair Darling will set out his plan to steer the country out of economic trouble.

He is expected to confirm the UK’s spiralling deficit will top £175bn this year, the combined effect of a costly fiscal stimulus and plummeting tax receipts.

The Tories ridiculed the efficiency proposals, saying they had all been announced before and accusing the government of failing to implement previous cost-cutting promises.