Drivers face rising fuel price misery after oil hit 70 US dollars a barrel for the first time in more than three years.
The RAC has warned further hikes in pump prices are likely to follow the rise in the cost of oil.
A litre of petrol has already increased by nearly 5p a litre since the start of November. Diesel has risen 3p.
Both are at a four-year high, averaging £1.21 for petrol and £1.24 for diesel.
RAC fuel spokesman Simon Williams said he was “fearful that 70 US dollars a barrel could become the new norm for 2018”.
He went on: “If oil stays at this level, pump price hikes will be almost inevitable.
“With households across the country still feeling the cost of Christmas, this is not the start to 2018 anyone would have wanted. It could also negatively affect business and further fuel inflation.”
The cost of filling up a typical 55-litre family car has risen by £4 for unleaded and £5 for diesel since July.
Petrol and diesel both cost £1.02 a litre in early 2016, but existing prices are still considerably lower than in April 2012 when petrol was £1.42 and diesel was £1.48.