Multi-million pound road and rail projects across the East of England are at risk in next week's Spending Review, it has been claimed.
But MPs and business leaders are hoping that money can still be found for key projects, such as the completion of the A11 dualling along the Norfolk/Suffolk border.
Another major regional project which could be hit is the £1bn scheme to widen and upgrade the A14 near Cambridge.
It is the main route from the container port at Felixstowe and the Midlands.
A public inquiry was about to be held into the plans but it was put on hold pending the outcome of the Review.
Matthew Hancock, MP for West Suffolk, said all the local MPs had been lobbying the government to dual the A11, a £134m scheme.
"It is a crucial project for the whole of East Anglia. The economic returns are 20 times the cost," he said.
Alex Plant, chief executive of Cambridgeshire Horizons, said that if improvements were not made to the A14 it would create "a problem for the country as a whole because of the freight going to the Midlands and the North".
"It should be a priority," he said.
Schemes in Bedfordshire which could be hit include the £25m Dunstable Northern Bypass scheme.
The A5 provides a route from Milton Keynes to the M1 at Junction 9, passing through the built-up area of Dunstable, which often experiences traffic congestion.
The plans for a dual carriageway have also been put on hold pending the Review.
In Cambridgeshire the key projects that could be hit are the A14 upgrade and plans for the £19.8m Chesterton railway station, north of Cambridge.
Mr Plant said the station was a vital part of the county transport scheme to encourage people out of their cars.
"I think Chesterton is such a strong project that there must be a way of making it work," he said.
Mr Plant said he was also concerned about the probable loss of grants for smaller projects such as cycle pathways.
Funding for A12 highway patrols - a dedicated police team on the road which links Ipswich and Colchester to London - is also thought to be in doubt under the terms of the Review.
Norman Hume, cabinet member for highways and transportation at the county council, said: "The A12 Patrols have had a tremendous impact in reducing congestion, helping the public by responding to incidents in an average of just six minutes and have dealt with nearly 4,000 incidents in the short time they've been operating."
Before the election there were also another £60m of improvements being looked at for the A12, but these projects remain on hold.
As well as concerns over the funding of A11, Norfolk businesses are concerned about the possible loss of funds for the £69m Norwich northern distributor road.
Caroline Williams, chief executive of the Norfolk Chamber of Commerce, said the A11 was the "number one priority for businesses".
But she added that the northern distributor was also vital to help "unlock a lot of development and growth" in the the north of the city.
She said potential for growth in this area had been restricted by traffic congestion in the area.
In Suffolk the two main projects which are being considered in the Spending Review are schemes to widen the A11 and A14.
Another plan that could fall foul of the Review is "Ipswich - Transport Fit for the 21st Century".
This £25m scheme aims to improve the way that people get around Ipswich and support future employment and housing growth in the town.
The scheme includes rebuilding bus stations, a state-of-the-art computerised traffic management and information system and real time bus information.
It will also include improvements to make it easier to walk and cycle around Ipswich town centre.