Petrol prices have risen for the ninth month in a row - piling yet more misery, says the RAC onto drivers.

The motoring organisation says motorists are facing 'relentless' increases in the cost of petrol and diesel at UK forecourts this summer.

Last month another 3.4p was added to the cost of a litre of petrol, and 2.7p for diesel, making it the most expensive July to fill-up since 2013 for drivers of petrol cars and since 2014 for those needing diesel.

The RAC had already warned earlier in the summer that families faced a significant increase in the cost of their summer holiday or staycation plans, because of the escalating costs of fuel.

On average a litre of unleaded now costs 135.13p – a price not seen since late September 2013. This is already up from 131.76p at the start of the month. Diesel meanwhile now costs on average 137.06p per litre, up from 134.36p.

It means that drivers filling up a 55-litre car with petrol face paying £11 more for a tank compared to just a year ago. For motorists filling their car with diesel, the cost for a full tank is on average around £10.40 more than it was last summer.

The RAC says with hopes building of a global recovery from the pandemic, vaccine programmes continuing to make progress and restrictions being eased in many places, demand for oil is increasing. And as that demand outstrips supply, wholesale fuel prices are being pushed up consequently pushing the costs onto drivers each time they fill up.

For those currently contemplating the cost of their holiday fuel bill, the RAC advises that drivers will find the 'best value' fuel at supermarkets this summer.

It says there, the price for a litre of petrol is around 3p cheaper compared to the average and will be 16p less than the cost of fuel at motorway service stations.

RAC fuel spokesman Simon Williams said: “Prices really are only going one way at the moment – and that’s not the way drivers want to see them going. With a second summer staycation in full swing, it’s proving to be a particularly costly one for many families who are using their cars to holiday here in the UK. With so many people depending on their vehicles, there’s really nothing drivers can do to escape the high prices, and our best advice is for them to drive as economically as possible in order to try to make their money go further."

Mr Williams said it was difficult to see a time when prices might begin falling again, with demand for oil only likely to pick up as countries try and emerge from the pandemic.

He explained: "Unless major oil producing nations decide a new strategy to increase output, we could very well see forecourt prices going even higher towards the end of the summer.

“If there is any good news at all, it is that prices would need to rise significantly further – by a further 3p – to reach the highest prices we saw in 2013. But that’s no comfort for the millions of drivers who are faced with paying so much more for fuel than they have done in many years."

In the next few months E10 petrol will also replace E5 as the standard grade of fuel in the UK because it is more environmentally friendly. But the roll-out is estimated to not be compatible with around 600,000 cars on the road in the UK and drivers are being warned to check.

Classic cars, or what the government also refers to as 'cherished' and older vehicles, some models of moped particularly those with an engine size of 50cc or under and some specific makes and models of car from the early 2000s are among those which may not be able to take the new petrol on board. Learn more here.

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