Centrica has launched legal proceedings against energy regulator Ofgem over the way it has calculated the incoming price cap on standard variable tariffs.
The company said it is not challenging the price cap itself and does not expect its implementation to be delayed.
But it is challenging Ofgem’s “decision not to investigate and correct its failure to enable the recovery of the wholesale energy costs”.
The company refused to rule out a judicial review when questioned by MPs last year.
In a statement, the company said: “We do not believe that a price cap will benefit customers but we want to ensure that there is a transparent and rigorous regulatory process to deliver a price cap that allows suppliers, as a minimum, to continue to operate to meet the requirements of all customers”.