I noticed this in France last month too!
Petrol's ridiculously expensive over there!
It's always been like that on the continent though. Their government's subsidize diesel because it's so many people us it as a fuel. You go to france, and most of the cars you see run on diesel.
And the serious question to why petrol costs so much. There's a few factors. The biggest part of it is fuel duty. Because driving is a necessity in todays modern britain (trains and buses are expensive, dirty, late, and crap), the government can milk lots of money from it, because people are willing to pay it. Then, there's the cost of oil, which, because it's sold in dollars, and the pound is pretty low, although getting better against the dollar, which makes it more expensive. And then, just because the government hates us so much, they whack VAT on the combined amount of petrol, and tax. That's right, you have to pay tax, on tax.
Because of all this, about 70% of the amount you pay for petrol now or something goes to Allistar darling and his little red briefcase, about 25% goes to the oil company's, and about 5% goes to the garage.
It's a very bad system, because it becomes exponential. If the price of oil increases, the tax increases. If this government cared for the 30 million motorists that use the road, then they might consider using all that money from the fuel tax, and VAT, and road tax, and congestion charges, and speeding fines, and parking fines, to make the road system a bit better, but alas no.