Confectioners in Saudi Arabia have sparked controversy with their latest sweet-sounding deal: a free litre of petrol for every customer who buys a chocolate bar.

Promotional posters throughout the capital, Riyadh, are touting the special fuel-with-snack offers from Snickers and several other chocolate brands, Saudi newspaper Al-Ektsadya reported on Monday.

But the promotions have spurred an outcry from Saudi economists who claim the giveaways exemplify the Kingdom's wasteful attitude to its oil reserves, the world's second largest. Local analysts have warned of economic disaster if Saudi continues its current high rate of energy consumption.

Chocolate bars typically cost between $0.25 and $0.50 in the Kingdom, while a litre of petrol retails for around $0.13.

“When companies grant free petrol for buying chocolate, it paints a powerful image of the waste of energy in the Saudi market," Rashed Abanmy, the head of the country's oil policies and strategic expectations centre told Al-Ektsadya.

"The use of gasoline as a free gift in shopping malls or for buying marginal products shows we are now dealing with energy in an irrational way,” he added.

Chocolate promotions are only the latest attempt by Saudi companies to boost sales of their low-price products by offering petroleum-related gifts.

Saudi Arabia uses the equivalent of 347,100 barrels of motor fuel a day. T he price of $0.8 per litre make it the third cheapest country in the world for petrol after Venezuela and Iran.

The largest oil-consuming nation in the Middle East, the Kingdom burns through more than 2 million barrels of crude per day, according to the US Energy Information Administration

(Correction: Prices of confectionery and petrol cited in the article were amended on 18 January)