The average price of both diesel and petrol went up again at UK forecourts during April, according to the RAC.
It said the average price of a litre of diesel was up for the fifth month in a row, by 0.62p, to 129.73p.
Petrol, meanwhile, was up for the sixth month in a row, by 0.89p, to 127.19p
According to the RAC, yet more price rises could be on the way, with the cost of a barrel of oil having risen by nearly $5 during April, which is set to translate to further pump price increases during May.
The organisation added that hopes for a recovery in demand for oil this summer could still push up prices even further.
RAC spokesman Simon Williams said the saving grace for UK fuel prices was the relative of the pound compared to the US dollar, with oil traded in the latter currency.
He added: “Progress in the global battle against the coronavirus will be critical in determining where fuel prices go from here.
“The success of domestic vaccination schemes could lead to greater demand for fuel and in turn rising prices due to global supply restrictions. Ongoing travel restrictions in other countries around the world may also prolong oil output restrictions and force fuel prices in the UK higher still.”