The Prime Minister said: “Some capital projects – for example on roads and energy, which are important, but not immediately vital will no longer go ahead as planned.”

Starmer said the extra defence spending would be funded by “reallocating spending from across government departments – reallocating capital budgets by one penny in every pound.”

Treasury documents released after the speech confirmed £700m of roads funding is facing the axe with the A38 Derby Junctions and A46 Newark Bypass schemes first on the block as the third Road Investment Strategy (RIS3) is reviewed.

DfT will also explore limited reductions to as yet uncommitted roads funding.

The Enquirer revealed earlier this week that National Highways has already cancelled its contract with Skanska to advance the A46 Newark Bypass project in the East Midlands.

Lincoln Labour MP Hamish Falconer said: “I am disappointed by the uncertainty today about the A46 Newark Bypass widening scheme.

“I support further funding for the DIP, but the A46 upgrade programme is well-advanced, long-awaited, excellent value for money and of strategic importance to both Lincoln and the region.

“Following the Labour Party leadership contest, I will be seeking an urgent meeting with the incoming prime minister, incoming chancellor and incoming secretary of state for transport to discuss this decision and explore whether there is a credible route forward for this vital project.

“I will continue to make the strongest possible case for the investment that both Lincoln and the wider region need and deserve.”