The Institute for Public Policy Research (IPPR) said there was no evidence of a "war on motorists", instead it was users of rail and bus services being hit by hikes in the cost of transport.
The IPPR report said the cost of motoring rose by 32.5% between 1997 and 2010, a real terms fall, but rail fares went up by 66.2% and bus and coach tickets increased by 76.1%. Train fares are set to rise further by an average of 6.2% next year after a surprise rise in inflation last month, with some tickets set to increase by more than 11%.
But the left-leaning IPPR said Chancellor George Osborne had announced delays in planned fuel duty rises which would cost £14 billion over five years.
The report recommended avoiding further delays in fuel duty rises and an extension of road tolls and congestion charging to finance public transport infrastructure.
Measures to improve bus and coach services, which the IPPR said were the most accessible forms of public transport, particularly in areas with poor rail connections, should be prioritised.
IPPR associate director Will Straw said: "No number of Taxpayers' Alliance petitions will change the facts. Compared to users of public transport, there is no war on motorists. Rail and bus users have seen fares spiral out of control while the cost of driving has actually fallen over the last decade."
A Government spokesman said ministers were determined to bring down the cost of running the railways but stressed it was also right to support motorists at a time of high oil prices.
He said: "The Government is embarked on the biggest programme of rail improvements since the Victorian era. Rail fares make a vital contribution to delivering these improvements. We have also rightly taken action to support motorists at a time of high international oil prices. Pump prices are 10p a litre cheaper than if we had proceeded with the planned fuel duty escalator."