A group of employees at TNK-BP have filed a lawsuit against Robert Dudley, the firm’s chief executive, accusing him of mismanaging the company. A decision will be made regarding the renewal of Dudley’s visa over the weekend. Gazprom says it may sue Belarus over unpaid debts for gas supplies. E.ON has begun construction of two gas turbines at a power station in Russia. Australian energy firm Nexus Energy plans to spend $975 million on exploration over the next three years to secure more gas reserves.