The average price of petrol and diesel at UK filling stations was almost unchanged during March, despite a rise in the wholesale cost of both fuels.
The RAC found that the cost of a litre of unleaded went up by just 0.06p, to 120.11p, and the cost of a litre of diesel by 0.01p, to 122.82p.
This meant the cost of filling a 55-litre family car was £66.06 for petrol and £67.55 for diesel.
The RAC said that retailers, previously criticised for increasing pump prices faster than they bring them down, appeared to have helped motorists, as the price of oil went up 5% during the month, resulting in the wholesale price of petrol rising by nearly 4p a litre, and of diesel by almost 2.5p a litre.
RAC fuel spokesman Simon Williams said: “It’s good to see fuel prices haven’t gone up as a result of the increased cost of a barrel of oil, which gained $4 in the second half of March.
“Retailers have clearly absorbed some of this cost, which is good news for motorists who had seen prices rise for three consecutive months from November to January.
“Looking ahead there is a glimmer of hope that motorists may be about to benefit from some cheaper forecourt prices in April.
“At a global level there is much going on, which may lead to a drop in the oil price: the developing trade friction between the US and China, increased oil production from fracking in the US and rising oil supply despite OPEC’s ongoing attempts to curb output.
“Each of these factors has the potential to cause the oil price to fall, which would almost certainly bring pump prices down.”
In terms of regional variation, the West Midlands saw the biggest increase in the price of unleaded with 0.54p being added to the price at its forecourts, taking it to 119.89p.
Motorists in the East saw their average petrol prices reduce the most, albeit only by 0.32p, to 120.63p.
The South East had the most expensive petrol at the beginning and end of the month at 121p a litre.
Despite diesel going up the most in Northern Ireland – 0.34p – motorists there were still paying the lowest prices for the fuel, a penny below the UK average at 121.71p a litre.
The South East had the most expensive diesel at 123.63p a litre.