The Ofgem enquiry found that there were two main issues for the high prices: high oil prices and declining UK gas supplies.

Ofgem has since written to Centrica, Shell, ExxonMobil and BP for information on whether their contracts prevented gas that was available from flowing into the UK market. "We are following this issue very closely," said CPI's head of environment, David Gillett.

Ofgem is due to meet with European Union (EU) representatives to discuss concerns about the way the European gas markets responded to rising prices in the UK.

Ofgem has written to the national competition authorities in Belgium, France, Germany and the Netherlands for their responses. "We are pleased that the companies Ofgem has contacted have agreed to co-operate fully, and that discussions with the EU are to be held shortly."

Gillett said although gas prices had risen in Europe they were much higher in the UK, with no obvious explanation. "This impacts on the competitiveness of the UK paper industry."

Story by Andy Scott