Oil prices jumped by 8.9 per cent to $50.45 a barrel yesterday after the Organisation of the Petroleum Exporting Countries (Opec), which pumps a third of the world’s oil, agreed to limit output for the first time in eight years.

Motoring groups warned that the agreement was likely to create an “unwelcome Christmas present” for families by sharply pushing up prices on the forecourt.

Petrol fell to 101p a litre in February after oil plunged to $27 a barrel as Iran increased production when sanctions were lifted. Some analysts now predict that oil could rise to $60 a barrel. According to estimates, this could push petrol to a two-year high of 123p a litre from 114p at present.

I think it will be a boost to global economic growth

It could pose a problem for Philip Hammond, the chancellor, by compounding inflationary pressures in the British economy, already on the march because of the falling pound. Higher oil prices could also push up household energy prices. Although not directly linked to wholesale gas prices, the two tend to track one another.

Mohammed bin Saleh al-Sada, the Qatari president of Opec, said that output from its 14 member states would be cut by 1.2 million barrels a day to 32.5 million from next month. The move, decided by all members at a meeting in Vienna, was aimed at improving the “general wellbeing and health of the world economy”, he said.

Khalid al-Falih, the Saudi oil minister, called it a “good day for the industry . . . and for the global economy. I think it will be a boost to global economic growth.”

Any significant rise in prices could add as much as 9p a litre — about £4.95 for a full tank — to the cost of petrol, according to the AA. The motoring organisation said it represented a double blow for motorists, coming at the coldest time of the year when cars used more fuel to power heaters, lights and windscreen wipers.

Petrol prices are already rising in Britain because of the weaker pound, which has pushed up the wholesale cost of crude oil, priced in US dollars. Opec’s decision comes a week after motorists were given a boost in the autumn statement, when the chancellor cancelled a planned tax rise and froze the fuel duty rate for the seventh year in a row. The move was designed to save motorists £130 a year at the pumps.

Luke Bosdet, an AA spokesman, said: “A long spell of higher prices, aggravated by a weak pound, could ravage family budgets as badly as the added cost of winter motoring.”

It was reported that Opec members were aiming for eventual prices as high as $55 to $60 a barrel to boost oil- dependent economies that have suffered two years of low prices.

The AA calculated that a rise of this margin could eventually push up petrol prices by as much as 9p a litre after accounting for VAT and assuming that exchange rates remained the same. It would take the present price of 114p a litre of petrol to 123p — equivalent to £4.95 added to the price of filling a 55- litre car, or £18 a month more for a family with two cars.

The RAC said that it would take about a fortnight for rises in wholesale prices to be felt on the forecourts. Simon Williams, the RAC’s fuel spokesman, said: “The oil price will react in the coming days and weeks, likely pushing pump prices up in the short term, but it is what happens into 2017 that will be most important in determining if the days of relatively low prices of fuel that drivers have benefited from this year are coming to an end.”