Chief secretary Danny Alexander said the Treasury was considering lobbying Brussels for a cut in fuel duty for motorists in remote rural areas.
Motorists in the Inner and Outer Hebrides, the Northern Isles, the Islands in the Clyde and the Isles of Scilly already receive a 5ppl discount on fuel duty.
Mr Alexander suggested the scheme could be included remote mainland communities. He was speaking during a visit to business leaders in Cornwall.
"We introduced, for the first time ever in this country, a fuel duty discount last year.
"I am looking at the moment at whether a case can be made to Brussels to allow a delegation for some of the most remote mainland areas in the UK as well.
But the process was a complicated one, Mr Alexander conceded.
"There's a very high hurdle in the sense that we have to be able to persuade the European Commission and get all of the other 26 member states to vote for it as well."
Mr Alexander added: "I can't make any promises at this point, but I am working on whether a justification can be made that is on the same basis as the justification for the islands.
"The case for the islands was made on the significant extra costs of delivering fuel to those areas.
"I'm not sure whether we will be able to do that [for the mainland] but I will certainly have a jolly good look at it."
Rural motorists have long complained that fuel prices are too high.
The news comes as HM Revenue & Customs figures suggest that high fuel prices and bad weather helped push down January's UK petrol sales to the lowest level in 23 years.
Drivers consumed 1.465bn litres of petrol last month, down 14m litres on the previous all-time low set in March last year and nearly 100m litres below December's consumption.
Against an average of 1.548bn litres in January 2012, last month's consumption fell 83m litres or 5.4%.
UK diesel consumption also fell in January, down to 1.923 billion litres for cars, haulage and other uses.
However, this is still higher than the all-time lows of 1.871 billion litres in January 2009 and then 1.833 billion litres in January 2010, when widespread and extended periods of snow cut road use.
AA president Edmund King said speculators had pumped up the wholesale price of petrol at a time of year when cars consumed the most and when concern was normally with imported diesel prices.
Currency gambling had devalued the pound, adding a further 1.6p a litre to the 7.9p-a-litre increase in the cost of wholesale petrol since the start of the year.
"This has broken the back of many family budgets and destroyed a great chunk of petrol demand," said Mr King.
"When the Government considers where it's going to get new revenue for the next financial year, it shouldn't knock on drivers' windows and demand more fuel duty – they have nothing left to give.
"Milking this cash cow has turned into flogging a dead horse."