The government has been urged to take action to get motorists out of their cars after the latest figures show ever growing traffic levels.
Critics say road network and public transport must be boosted
Statistics from the Department of Transport show car traffic rose nearly 2% year on year in the first three months of 2004.
The Liberal Democrats warned Britain was becoming "a gridlocked nation".
The RAC called for more investment, and warned of the risk that roads would no longer cope.
Liberal Democrat transport spokesman John Turso said it was time for ministers to make a real commitment to cutting traffic levels: "The government needs to give motorists a real incentive to get out of their cars," he said.
"Until we have a safe reliable and affordable public transport system, the roads will remain congested."
The executive director of the RAC Foundation, Edmund King, voiced his hope that the latest figures would act as a "wake-up call" for the government to rethink its policy.
He said "significant and sustained investment" into road network was needed to prevent "total gridlock".
Mr. King also pointed out that road traffic had grown by 75% between 1980 and 2002, while the total length of roads had only gone up by 10% in the same period.
"Road users currently pay £44bn a year, of which less than £6bn is spent on roads," Mr. King said.
"We claim to be the fourth largest economy in the world, so surely we can afford a decent road system to support economic growth," he added.
Friends of the Earth transport campaigner Tony Bosworth warned more congestion would lead to more pollution and emission of gases causing climate change.
"It is time the government... put more money into giving people better public transport and safer streets for cycling and walking, rather than building and widening roads," he said.
Meanwhile, the M1 northbound was closed in Northamptonshire on Thursday after a serious accident involving two lorries, one of which carrying a chemical.
Reports said drivers had been stuck in tail-backs for up to five hours.