Sharp falls in the value of Sterling in recent weeks could trigger a rise in fuel prices of perhaps 5p per litre before the end of October, according to the Petrol Retailers’ Association (PRA) and RAC.

Brian Madderson, chairman of the PRA, forecasted a rise of 4-5p per litre by the end of the month, while RAC predicted a more conservative 3p per litre increase.

Nevertheless, the impact of such a pump price rise on fleet fuel bills will be significant with Mr Madderson saying: “The double impact of the pound weakening against US$ and global oil prices strengthening will cause pump prices to move sharply upwards.

“The pound has now fallen by more than 15% to $1.24 since the pre-Brexit level of $1.47.

At the same time, renewed talks amongst OPEC members’ trying to curb oil production has led to a hardening of global oil prices with Brent Crude passing the psychological barrier of $50 a barrel.”

As a result, wholesale costs to retailers have increased by more than 6p per litre for petrol and 7p per litre for diesel in the last few weeks. The UK average pump prices has only increased by less than 2p per litre for both grades over the same time period so further rises are forecast

by the end of the month.