FairFuelUK says the UK government's criticism of fuel companies for not passing on lower oil prices at the pumps has "a whiff of hypocrisy".
The campaign group says a 3p duty cut in tomorrow's (3 December 2014) Autumn Statement is what's needed to boost the economy.
FairFuelUK points out that two-thirds of the cost of every litre of fuel goes to the treasury.
"I'd hate to think all this tough-talking to the oil companies is a smokescreen to hide the real issue that, at the pumps, it's the government that takes the most," says Quentin Willson, FairfuelUK campaigner.
"Trying to deflect attention away from our calls for a 3p duty cut in the Autumn Statement would be unforgivable."
The group is reiterating its call for the duty cut, saying the UK has the highest fuel duty regime in the EU.
Richard Burnett of the Road Haulage Association – a supporter of the campaign – says diesel represents more than a third of a haulier's costs, adding that a 3p cut in duty would equate to "a 3-4% reduction in costs to the haulier, enabling them to be more competitive".
He adds: "A duty cut of 3p litre is fair, balanced and achievable."
