BUSINESS leaders have pressed the Government to increase spending on roads amid warnings that the economy is being hit by the country's overstretched infrastructure.

It comes as Chancellor George Osborne prepares to announce a £1bn upgrade of the M4 as part of the comprehensive spending review in June.

Ministers are also considering major upgrades to the A1 north of Newcastle, improving links between London and Scotland, the A303 in southwest England and the A47 running through the Norfolk Broads.

A survey by the EEF manufacturers organisation showed that most businesses want investment in roads ahead of high-speed rail.

The poll of more than 200 manufacturers also revealed frustration with the coalitions policy on airports, saying that decisions on future capacity should be speeded up.

Half of companies said their operating costs were significantly increased because of the state of the country's roads.

Fewer than one in four of those questioned said investment in high-speed rail was important to their companys growth.

The EEF called for an independent infrastructure commission to be set up, and said a greater share of public spending on transport should be allocated to roads.

Roger Salomone, the EEF's head of business environment policy, said: "Political prevarication and policy reversals have left Britain in the slow lane in developing its infrastructure for decades. Government must reassess its investment priorities, act faster on major issues like airport capacity and take the politics out of infrastructure by setting up an independent commission.

"In particular, the road network is the backbone of the economy but it has been neglected.

"We are now feeling the ill effects, with the majority of firms reporting that the state of the nations roads is significantly increasing their operating costs. Investment should be targeted at shovel-ready maintenance projects and bringing forward upgrades to heavily-congested arteries.

Furthermore, world-class air links are critical to export-led growth and attracting inward investment. To keep up with the competition, we need investment across the board, in Heathrow and in regional airports.

"Maintaining our status as a global aviation hub is critical to our international standing and expanding runway capacity at Heathrow is the most viable way to secure this."