U.K. fuel prices hit an all-time high of £1.40 ($2.2) a liter this week, further hammering motorists ahead of a fuel duty increase in August.

According to figures from industry analysts Experian Catalist, drivers were paying an average £1.42 a liter, as fears over Iranian supplies have seen the price of crude oil soar more than 12 percent since January.

The rise comes as the British government confirmed this week it will proceed with a 3 pence per liter fuel duty increase on Aug. 1.

A figure of £1.40 a litre is a massive price for people to have to pay and there is no end in sight to rising prices, RAC technical director David Bizley told the BBC.

The way things are going the planned duty rise will see average petrol prices hit the £1.50-a-litre mark - forcing more and more people who need their cars off the road.

Earlier this week, British Chancellor George Osborne confirmed the duty rise as he outlined next year's budget plans.

It shows just how out of touch George Osborne is that, in this week's budget, he said he could afford to give a huge tax cut to people earning over £150,000, but couldn't afford to cut fuel duty for middle and low-income families feeling the squeeze, said Labour's Treasury spokeswoman, Cathy Jamieson, according to the BBC.

While fuel costs are expected to continue rising, there was some good news for consumers: The Bank of England said it expected inflation to slow this year.