The Daily Mail newspaper in London reported that BP was in "secret talks" with Gazprom to expand the twin Nord Stream pipeline to Britain. It quotes BP director for Russia David Peattie as saying talks were in the "early stage," though British Prime Minister David Cameron is said to favor the proposal.
Gazprom said in June that it was considering a possible role for BP in the Nord Stream network.
Nord Stream, running through the Baltic Sea to Germany, is part of a network of pipelines planned by Gazprom to diversify Russian natural gas exports to European consumers.
Recently, the European Commission said it launched an anti-trust investigation into Gazprom's practices in the region.
The Daily Mail reports a 600-mile extension for Nord Stream could be completed by 2014. The British government is said to favor a deal that would make Gazprom the second-largest natural gas supplier in the country.
Both of the existing Nord Stream lines are designed to transport about 1.9 trillion cubic feet of natural gas. The first leg of the pipeline system went into service last year.