LONDON - UK carbon trading and advisory firm CF Partners has launched an 82 million euro lawsuit against Barclays Plc claiming it misused confidential information to clinch a takeover of a rival firm last year, an allegation the British bank rejected.

CF Partners said it had issued proceedings against both Barclays and Tricorona, a Swedish carbon credits trader that was bought by Barclays for 98 million pounds in June 2010.

"We have never taken legal action before and have only commenced litigation after very serious consideration," said James McRobbie, general counsel for CF Partners. He said proceedings were only started after attempts to directly resolve the matter had failed.

A spokeswoman for Barclays said: "This case is without merit and we will be contesting it vigorously.

"Barclays had no contractual relationship with CF Partners and did not enter into any advisory mandate," she added.

McRobbie declined further comment, but a copy of the lawsuit shows CF Partners claims that it identified Tricorona as an attractive takeover prospect and in around August 2008 it approached Barclays, initially as a potential debt provider.

Over time the bank provided additional advisory roles and CF provided Barclays and Tricorona with confidential information, the lawsuit said.

Barclays is one of the biggest players in the carbon market, and a person with close knowledge of the case said as such it would have known about Tricorona and its portfolio through that activity.