The Liberal Democrats have blamed Brexit and the subsequent fall in the value of the pound since the vote for a 5ppl increase in the cost of fuel over the period, something they claim will be a longer term trend despite the current respite in UK pump prices.

As the parties build up to next month’s general election, the pro-EU party has said the UK's vote to leave the union is responsible for 5ppl of the recent increase in the cost of diesel (although fuel prices at the pumps are currently in reverse thanks to a supermarket price war, which has seen a series of cuts in the past week).

According to the AA, in July 2016 the average UK diesel price was £112.7ppl. Last month (April 2017) it stood at 121.8ppl. An update as of 5 May, recorded the average diesel price at £1.20ppl as the current round of supermarket cuts took effect.

This, the Liberal Democrats claim, could see hauliers paying around £2,200 per year more to run the average lorry (based on the assumption that the latest round of supermarket price cuts will not be maintained long term).

Nick Clegg, the Liberal Democrat’s Europe spokesman, said: “Theresa May claims that Brexit is going to be a great success. The reality is it’s going to make us poorer. The effects are already being felt.

"The rise in fuel costs will push up prices in the shops. This means consumers are going to be hit twice, once at the pump and again at the checkout.

“The Conservatives are driving the country towards an uncertain future. Their extreme interpretation of the referendum result will see us yanked out of the single market, our best guarantee of economic stability. They are deliberately planning to put an end to barrier-free trade with the continent.

“The consequences of this are going to be felt not by the wealthy elites but by ordinary people up and down the country.”

The chancellor froze fuel duty in the March budget but resisted calls by FairFuelUK for a cut.