The battle for control of Crédit Lyonnais stepped up a gear when the bank revealed that Crédit Agricole had overtaken BNP Paribas to become Crédit Lyonnais' biggest shareholder with a 17.4% stake.

The news comes as Jean Peyrlevade, chairman of Crédit Lyonnais, prepares to chair a board meeting on Wednesday to discuss the bank's future strategy. Only two weeks ago, Gilles de Margerie, chief financial officer of Crédit Agricole, said the bank was still considering making an offer for its smaller rival "at a reasonable price".