HOUSTON, March 13 (Reuters) - The Federal Energy Regulatory Commission on Wednesday asked liquefied natural gas developer Venture Global LNG to explain the basis for its extensive filing of confidential documents in its Calcasieu Pass LNG export terminal.

Venture Global LNG customers have protested to FERC that they have been unable to understand why the Louisiana plant has not provided contracted cargoes because of the company's filing of confidential documents to the energy regulator on plant construction and repairs. (Reporting by Curtis Williams)