National road tolls could be brought in within a decade, Transport Secretary Douglas Alexander has said.
There are about 33m vehicles on British roads, said Mr Alexander
He admitted a "still sceptical" public had yet to be won over to the benefits of road pricing - but said something had to be done to prevent gridlock.
Drivers needed first-hand experience of road pricing through pilot schemes in Manchester, Birmingham and elsewhere within the next five years, he said.
Last week a transport study suggested road charges could halve congestion.
The Treasury-commissioned study led by former BA chief Rod Eddington said road pricing could benefit the economy by £28bn a year.
'Car park' gridlock
Asked whether road pricing was inevitable, Mr Alexander told BBC One's AM programme that it was a "debate that we need to have" and said Sir Rod's report was a major contribution to that debate.
He said the number of vehicles on British roads had gone up from 26 million in 1997 to 33 million. Ministers fear that congestion could rise by up to 25% by 2015 in big towns and cities, if nothing is done.
"Unless we're going to face the alternative of US-style gridlock with some of our busiest roads simply becoming car parks then action is necessary."
But he ruled out more road-building programmes as a solution, saying: "I think most informed commentators realise we can't simply build our way out of the challenge of congestion."
He said the government was working closely with the regions involved in trial road-pricing schemes and were expecting bids by next summer.
It would mean regional pilots within the next four to five years, and the possibility of a national scheme in about a decade's time.
But he added that people had to be given more choice about how to get around.
"I have always believed the only circumstances in which road pricing could be judged a success was if it was partnered with proper investment in public transport," said Mr Alexander.
Making more room on the railways, for example through longer trains or possibly double-decker trains, might be one way of offering people more choice of transport, he said.
Speaking later, shadow chancellor George Osbourne said the Conservatives were "sympathetic" to road pricing.
He said he could see the M6 toll road had brought "great benefits" to the West Midlands.
But he added: "I think road pricing should be linked directly to improvements in transport infrastructure and should not be used as an excuse to increase the overall level of taxation."