Cost of Fuel In Belgium

I’ll be driving to Belgium next week via Dunkirk and so I am wondering if anyone here can point me to a website that shows the costs of filling up in Belgium. I’m usually running on reserve by the time I arrive in France – where I’m expecting to pay about 1.08 euros per litre of DERV (or about 74pence a litre) – but, as I’ll be crossing the border into Belgium within half an hour of my arrival in France, I thought I’d ask the board for some cost saving tips?

Thanks in advance.

Cheers

Mayfly