Diesel prices hit a six-year low

The average price of diesel has reached a six-year low, new figures show.

The price fell to 109.86p per litre on Monday, according to RAC Fuel Watch data.

This is the lowest price since late December 2009.%VIRTUAL-ArticleSidebar-motoring-guide%

November also saw a return to petrol being sold for under £1 a litre, with Asda cutting its price to 99.7p in a three-day promotion.

The average price across all fuel retailers fell for the fifth month in a row, from 107.67p at the start of the month to 106.98p at the end.

The figures mean the cost of filling up a 55-litre family car with petrol has plunged by £7.75 compared to a year ago, while a tank of diesel is £8.95 cheaper.

Lower prices have been attributed to crude oil tumbling to 40.40 US dollars, its lowest level since February 2009.

RAC Fuel Watch spokesman Simon Williams said: "While petrol for under a pound a litre has become a reality at the cheapest retailers we would like to see this happen on a non-promotional basis.

"This depends, of course, on the cost of a barrel of oil staying low and ideally trading down a little closer to 40 US dollars for longer - something which is very hard to predict."