The MP for East Worthing and Shoreham Tim Loughton has warned the Government that today's announced improvements to the Chichester by-pass could just create more traffic jams around Worthing and Arundel.
The Tunbridge Wells MP Greg Clark has welcomed the Government's decision to go ahead with improvements to the A21 between Pembury and Tonbridge.
AA roads policy head Paul Watters said: "Drivers will be delighted to hear of the bold plans but hope this won't be let down by slow, patchy delivery. Potholes are here and now and our traffic jams just get worse.
"We welcome plans to transform the Highways Agency into a public corporation with a clear brief and guaranteed funding free of political intervention. But UK drivers remain fearful of paying more to use our roads - after all, they already contribute £46 billion each year in tax.
"If new schemes involve tolls they will be highly contentious and, while adding motorway lanes is very welcome, pinching the hard shoulder to do this may be regarded by some as doing this on the cheap. Overall this is very good news today, but the devil will be in some of the detail."
RAC Foundation director Professor Stephen Glaister said: "We welcome today's pothole pledge, recognising the importance of maintaining the roads we have with building the new roads we need.
"But the timetable is critical. We are still talking about action taking place over the medium term, not today and tomorrow. And we still don't know exactly where the money is coming from. We have been waiting more than a year for a review of road funding to be published. That wait continues.
"Crucially, by giving the Highways Agency corporation status, the Government is finally acknowledging the need to set long-term plans for our strategic roads, just as they have always done for the railways."