Members of a fuel price lobby group have urged the government to be more open about how much money it takes when a motorists fills their tank.

Quentin Willson of the FairFuel UK campaign displayed a huge mock-up of a petrol and diesel receipt outside Parliament in order to reinforce the message that drivers want to know exactly where their money is going.

The receipt contained an accurate cost breakdown that highlighted how much VAT and fuel duty had been charged.

Mr Willson wrote in a blog post that he would like the government to adopt a more honest approach, but fears the authorities are "embarrassed" to admit they pocket 60 per cent of every fuel transaction.

"We need the government to set an example by being open about how much it takes from every litre of petrol and diesel we put in our tanks," he wrote.

Last month, the AA revealed that petrol consumption has fallen to record lows in the UK this year, as many motorists have been priced off the road.