Council chiefs have called on the Government to release billions of pounds of EU regeneration funding that could finance infrastructure projects, including new roads and bridges.
Local areas in England have put forward proposals to win a share of £5.3bn of EU regeneration cash up until 2020, which had been secured before Brexit.
The European Commission building in Brussels
However, much of this cash now appears to be held up in Whitehall awaiting ministerial sign off, raising the prospect of projects being stalled and local areas losing out on the expected monies.
The Local Government Association (LGA) estimates billions of the EU funding has yet to be released, with Cornwall and the North-east having only received 20% of their funding allocations and Birmingham 25%.
Councils have expressed concerns that Whitehall could hold onto any money not already diverted to local areas, following the economic uncertainty caused by the vote to leave the EU.
Lord Porter, LGA chairman, said: 'Communities and local economies have become increasingly reliant on what EU funds can achieve for them. Councils have used EU funds to help new businesses start up, create thousands of new jobs, roll out broadband and build new roads and bridges.
'Losing any of this vital money over the next few years would be a real blow for local economic growth and communities.
'It is important for the Government to end the current uncertainty and guarantee that local areas will receive all of the EU funding they have been allocated by 2020, regardless of whether decisions over which projects it should be spent on have been made or not.
'An urgent government commitment to protect all of this funding is imperative so local areas can get on with the vital task of creating jobs, building infrastructure and boosting growth.'