Petrol should be made more expensive to reduce vehicle emissions linked to global warming, a group of MPs says.
Petrol price rises are massively unpopular with drivers
The Environmental Audit Committee has called on ministers to use increases in fuel tax to subsidise public transport and alternatives to conventional fuel.
The report said recent data showed the government's Climate Change Strategy is "seriously off course".
Government policies have yet to make a "significant impact" on predicted UK carbon emissions, it said.
Emissions relating to transport, which accounts for over 30% of all energy consumption, are "still moving in the wrong direction".
"We urge the government to implement the planned rise in
fuel duty at the earliest opportunity," the MPs said.
"The government must use the fiscal incentives at its disposal to curb transport growth while at the same time ensuring that there is sufficient investment in low-carbon public transport systems."
It argues that despite the current high crude oil price, petrol is still relatively cheap in real terms and argues the case be made for increasing fuel duty.
But the latest Budget "fails to take forward the Treasury's strategy of shifting the burden of taxation from 'goods' to 'bads'", the report said.
Chancellor Gordon Brown postponed this year's planned increase in fuel duty because of the high price of crude oil.
High petrol prices led to widespread protests in September 2000 which brought much of the UK to a near-standstill.
The MPs also criticised the Treasury for failing to do enough to promote more efficient use of energy in people's homes.
Ambitious targets for reducing emissions through energy efficiency measures such as insulation were unlikely to be realised, they suggested.
Under the Kyoto Protocol industrialised countries have committed to cut their combined emissions to 5% below 1990 levels by 2008/ 2012. EU countries are expected to cut emissions by 8%.
Britain should meet these targets, but there were growing doubts the government's voluntary target to reduce carbon dioxide emissions by 20% by 2010 would be met, the committee said.
Committee chairman Peter Ainsworth said the "key problem area is transport".
"If the government's commitment to sustainable development is to be taken seriously, it must take more radical action.
"There is an urgent need to look afresh at the scale of the challenges we face and develop and adequate response."
The committee report was published on the same day as the government announced recycling rates in England had reached record levels.
Recycling rates of household materials like paper, compost, glass, plastic and tin reached 14.5% in 2002-3 - up 25 on 2001-2 figures.
The government says the achievement will help the country meet its target of recycling 17% of household waste by 2003-4.
Environment minister Elliot Morley said people were recycling more than ever, but a significant minority needed to do more.
The recycling target increases to 25% by 2005-6, and the Local Government Association is warning that local councils' waste budgets are already being squeezed.