After paying the mortgage, many working families spend more on transport and commuting costs than any other expenses.
The RAC Foundation has calculated that the rise in oil and fuel costs is now forcing households to make some severe economies. Road users are also the only commuters bearing the cost of reducing their carbon emissions under pollution initiatives.
Sheila Rainger, acting director of the RAC Foundation, said: "UK households are under increased financial pressure as energy and other household bills are at an all time high.
"Fuel should not be priced as a luxury or be considered an undesirable purchase, as car travel is essential and in many instances the only way for people to get to employment, education and health services."
The RAC Foundation is adding to a growing list of financial advisers and pressure groups who hope to appeal to the chancellor, ahead of the Budget, to cancel the planned rise in fuel duty, which was announced last year.