The Lib Dems have committed to spending £300m over the next Parliament to fill 1.2 million potholes a year.

It said it would redirect funds from the road building budget.

Lib Dem leader Sir Ed Davey said: ‘Only the Lib Dems have a real plan to fix the state of our roads by giving the money to councils, who know their roads and are best placed to fix them.'

But RAC head of policy Simon Williams said: ‘While we agree with the premise of guaranteeing councils more road funding, the real question is whether the Lib Dems – and indeed the Labour Party – would ensure the £8.3bn of funding the Conservatives had reallocated from HS2 to fix local roads is still given to local authorities should they win power.

‘Without this sum, which itself is only enough to resurface 3% of all England's council-run roads, the Lib Dems' promised £300m won't even scratch the surface of the UK's pothole problem.'

Labour has pledged to fix one million potholes a year if elected on 4 July.