Gap is 'widening' between price of petrol and diesel
As fuel costs continue to rise, the price difference between diesel and petrol is widening.
On average, filling up with diesel will cost you at least 7p a litre more than unleaded according to AA figures.
That's the biggest the gap has been in three years.
The Road Haulage Association (RHA), which represents truck drivers across the UK, says the fuel industry has questions to answer about the rising cost of diesel.
It could also hit drivers who swapped petrol for diesel in an effort to save money.
Mark Wright lives in Walsall and has just bought a van to try to get his gardening business going.
He's already noticed how much diesel costs.
He said: "It's ludicrous. Just looking 12 months back, it's probably gone up by 20p a litre.
"It's having a massive impact. It's costing so much more to run the vehicle and it eats into any profit you do make."
How has the price of fuel gone up?
Why is diesel getting more expensive?
- More demand - Last year nearly half of all new cars sold in the UK ran on diesel, compared to just one in six in 2000. Diesel is also more expensive in the winter because more oil is needed for heating homes.
- Less supply - Oil refineries across Europe say they have been struggling to produce the fuel needed to meet this extra demand. One of the biggest refineries in the UK is at risk after the company that owns it went bankrupt.
- Tax - In the UK, diesel and petrol are taxed at the same rate, unlike many other European countries. Fuel duty was due to go up this month but that was delayed by the government to try to help motorists out.
Is it worth getting a diesel car?
A diesel car costs more than the same model running on petrol - around £1,000 for a new small car.
But diesel goes a lot further, so it should work out cheaper if you're doing enough miles.
Andy Gore recently swapped his petrol car for a diesel because he commutes more than 100 miles a day.
"It was costing me £500 a month and now it's costing around £360, although obviously it's going up and up all the time so I'm incurring the cost."
If you're doing lots of miles on the motorway and plan to keep your car for a few years, you might be better off with a diesel.
If you tend to do short journeys and don't travel more than about 18,000 miles a year, petrol is probably a better bet.
Andy Gore isn't regretting the switch yet.
"I like my car," he said. "But when you see how the gap's going, it's going to get to a stage where you might as well stick with petrol."