The price of both petrol and diesel from UK forecourts went down in June after four months of rises, according to data from the RAC.
It found that the average price of a litre of petrol went from 130.67p to 127.62p, while the average litre of diesel went from 135.51p to 130.90p, with the latter the ninth biggest monthly drop in diesel prices since 2000.
The RAC says the price cuts were due to a drop in the cost of oil.
However, it also says petrol prices did not drop as far as they should have: when the wholesale cost of the fuel was the same in March as at the end of June, the average litre was more than 4p cheaper.
RAC spokesman Simon Williams said: “It’s great to see pump prices falling for the first time since January, but the reductions should have been greater based on the substantial decrease in the wholesale price.
“Retailers were clearly banking on the oil price rebounding after its sudden drop. Inevitably this has meant bad news for drivers who have lost out with pump prices being 4p a litre more expensive than they should have been.
“Unfortunately, retailers’ hunch that oil would quickly increase again were right and now their prices are broadly where they should be based on the current wholesale price. They just happen to have made significant profits as a result of not passing on more of the savings to drivers than they did.”
Williams added that further drops in the price of oil were unlikely.
He said: “Drivers should take heart from the fact fuel prices have gone down in June, but it’s hard to see another drop materialising with Opec and its partners extending their production cut until March 2020.
“On top of that there is also talk of a trade deal being struck between the United States and China, allaying fears of a global economic slowdown which may have led to lower oil prices and in turn cheaper prices at the pump.
“If we get through July without petrol and diesel going up it will be a good result for drivers at the start of the summer holidays.”