This is the question I do not want to have to ask George Osborne on Budget day, 22 June. As the chancellor will know, it is also the question he repeatedly asked the previous chancellor, Alistair Darling, each time Mr Darling refused to divulge the implications of the then government’s budgetary forecasts for spending departments.

Mr Osborne asked the question last December after the pre-Budget report.

Mr Osborne asked the same question in Parliament in the debate on the March Budget.

It was the same question Mr Osborne asked on the radio last September when he revealed a leak of internal Treasury documents. “It’s about trust and honesty,”  Mr Osborne said.

And in March he wrote to Sir Nicholas Macpherson, the permanent secretary to the Treasury, to explain why its projection for departmental spending was vital to a public debate on the public finances.

“Given the absence of a spending review, this information is the very least that should be provided in order to facilitate proper scrutiny of the government’s plans at the election”.

Before being in government, it seems that Mr Osborne was almost obsessed about getting an answer to the DEL/AME split question. So, a simple test for the Budget will be the degree of transparency Mr Osborne introduces to projections for public spending. Given this past commitment to trust and transparency, I fully expect the following:

• The chancellor will publish Treasury projections for total government spending
• The chancellor will publish projections for debt interest
• The chancellor will publish projections for other spending over which he has no control such as accounting adjustments
• The chancellor will publish projections for social security bills on the basis of unchanged policies
• The chancellor will publish the implications for the former for departmental spending totals.

Anything less than this would Read more