Independent companies including Enron Europe, United Gas, Bell Gas and Caledonian Gas have written to MPs calling for a separate company and management to be established. They argue that without separation there is no guarantee of fair play for British Gas rivals which need to use the pipes.
British Gas has created a pipeline arm, Transco, and established Chinese Walls between this and the gas supply businesses. Its rivals say that experience shows that Chinese Walls within a large company do not always work.
The debate has taken on a significant political dimension with Labour opposing the amendment, laid down by Conservative backbencher Alan Duncan. The party said that the disruption of setting up a separate subsidiary could threaten the smooth introduction of competition in the domestic gas market.