Tories and Labour warned over ambitious spending promises

Returning infrastructure investment to 1970s levels may be undeliverable, says IFS

Labour and the Conservatives have triggered a public spending bidding war, promising massive programmes of borrowing that will return public investment to levels last seen in the 1970s, according to Britain's leading experts on the public finances.

The Institute for Fiscal Studies said plans unveiled by Sajid Javid, the chancellor, and John McDonnell, his Labour shadow, would represent a decisive break with the past, but warned that a future government might have trouble delivering projects on the scale envisaged.