Tumbling oil prices have pumped £10.7 million-worth of savings into the fuel budgets of Alphabet customers and their drivers in the UK since September.

The cost of refuelling the 122,500 cars in Alphabet’s combined vehicle portfolio of 131,000 cars and commercial vehicles has fallen by up to £750,000 a week.

At the end of January 2015, Alphabet calculated its vehicles were using £4.3 million of petrol and diesel a week, compared to £5.0 million in September 2014 and nearly £5.5 million a week in 2013.

At the end of January 2015, Alphabet calculated its vehicles were using £4.3 million of petrol and diesel a week, compared to £5.0 million in September 2014 and nearly £5.5 million a week in 2013.

Mark Gibson, head of marketing and business development at Alphabet cautioned fleet operators not to plan on fuel prices staying down for the long term.

He said: "Non-OPEC oil producers are already cutting jobs and capital expenditure deeply, which will feed through as reduced supply later this year.’

"Once the current excess inventory is used up, the oil price is expected to climb again as demand exceeds supply, followed by an increase in the cost of diesel and petrol."

Gibson added: "The big picture to keep in mind when developing the plans for the future of your vehicle fleet is that the worldwide number of vehicles has increased by 35% since 2005, while the supply of petroleum fuel has only risen by 12%. Therefore basic economics suggests that the periods when fuel prices reduce in future will be the exception, rather than the rule."