Nine million motorists will lose out when the government introduces its controversial road tax reforms in 2010, new figures have revealed.Gordon Brown was today accused of misleading MPs in the Commons over the changes, which were only meant to penalise 'gas-guzzling' vehicles. Last month the Prime Minister told parliament that most drivers would be better off under his new scheme. But the treasury's latest financial predictions prove that 43 percent of motorists will pay significantly more.Experts say the exchequer will rake in more than a billion pounds in extra revenue from the scheme by 2011.The Chancellor Alistair Darling only avoided a Commons rebellion last week when he assured Labour MPs he would look again at the reforms, which are likely to hit drivers of older family cars hardest.Today Edmund King, the AA President, said: "This is not a green tax. but a mean tax that will hit millions of hard-up families."Sheila Rainger of the RAC added: "This scheme will take £1.2 billion off the motorist and put it in the Treasury's coffers. The Chancellor must think again."Darling has been condemned for pushing the road tax reforms though under the radar after he failed to mention them in his Budget speech in March.