Shell Petroleum Development Co. Ltd., in a statement from The Hague, said it was unable to meet contractual volumes on natural gas supplies to a Nigerian liquefied natural gas system because of a leak on its Eastern Gas Gathering system in Rivers States, near the Niger Delta.
Shell said about 1.5 billion cubic feet of natural gas per day was affected by the declaration.
Nigeria Liquefied Natural Gas Ltd. spokesman Kudo Eresia-Eke said "the shutdown will be in place until the source of the leak is identified and necessary remedial actions are completed," Nigerian newspaper ThisDay reports.
Shell has previously declared force majeure on oil deliveries from Nigeria because of sabotage against its pipeline networks in the Niger Delta. The region's militant Movement for the Emancipation of the Niger Delta is said to be preparing a new offensive at the end of the month.
Nigerian President Goodluck Jonathon this week declared a state of emergency for three northern states because of militancy tied to Boko Haram, a group with ties to al-Qaida.