15:41 11 December 2015
For the first time since 2009, the price of Brent crude oil fell below $40 a barrel earlier this week. The RAC said that if retailers "do the right thing" and decide to pass on the savings to customers, there should be a 3p a litre drop for petrol prices and 5p for diesel before Christmas.
RAC spokesman Simon Williams, said: "All we need is for the supermarkets to do the right thing and embrace the season of goodwill by passing on those savings at the pump to make Christmas that much cheaper for everyone."
He added: "We are still some way off the average price of unleaded reaching the £1 a litre mark but this will be a big step in the right direction."
"If retailers don't pass on the savings quickly, they will be giving themselves an unpopular Christmas boost to profits by pocketing the extra margin when they should really be passing this on to their customers instead."
Since June 2014, oil prices have gone down from more than $115 per barrel to under $40 on Monday.