The price of diesel rose by 10p a liter to an average of 190.5p – the third-worst monthly increase on record, behind previous rises this year, according to figures from the motoring group. The RAC said a full tank of diesel rose by more than £5 to £105 as prices threatened to rise to an all-time high of £199.09 a liter at the end of June. The figures showed the price of petrol rose, although less than diesel – up by almost 4p/litre from 162.67p to 166.38p. This meant a full tank costs £2 more at £91.51. Britain had experienced a softening of prices at the pump over the past three months, following record prices held earlier this year as Russia’s invasion of Ukraine pushed up the cost of oil. But the OPEC+ oil cartel and its allies agreed to a larger-than-expected cut in production targets by 2 million barrels per day last month, sparking a clash with US President Joe Biden. The decision, led by Saudi Arabia and Russia, sent oil prices sharply higher, from around $89 a barrel to nearly $95. Prices peaked at $138 a barrel in March just after the war began and remained above $100 through the spring and early summer, putting pressure on the pumps. The record prices prompted claims that fuel retailers were profiteering and the Competition and Markets Authority raised concerns about oil refiners’ profit margins. The fall in the pound as a result of the political turmoil in Westminster last month also made wholesale petrol and diesel – which is traded in dollars – more expensive. RAC fuel spokesman Simon Williams said: “After three months of falling pump prices, October was a major shock to the system for drivers with the unwelcome return of some scary numbers on suburban totems. “The fear now, particularly for diesel drivers, is that the average price of a liter will return to the record 199.09p which made a full tank cost more than £109. Looking at the wholesale market, we strongly hope that the price should stabilize.” Subscribe to Business Today Get ready for the business day – we’ll point you to all the business news and analysis you need every morning Privacy Notice: Newsletters may contain information about charities, online advertising and content sponsored by external parties. For more information, see our Privacy Policy. We use Google reCaptcha to protect our website and Google’s Privacy Policy and Terms of Service apply. Williams urged drivers to shop around for the best price and not assume traditional discount supermarkets would be the cheapest. RAC data showed members-only retailer Costco was the cheapest place to fill up. It sold a liter of petrol for an average of 154p and diesel for 176p – 12p and 14p lower than UK averages. The OPEC+ decision angered Biden, who had hoped to persuade Middle Eastern countries not to cut supplies to curb fuel price hikes and soaring inflation.