OSLO, May 16 (Reuters) - Norway's Hammerfest LNG plant faces more delay before it can restart production following a fire in 2020, Norwegian gas system manager Gassco said in a regulatory filing on Monday.

The plant, which is operated by Equinor, is now expected to resume output on May 23, the filing showed, six days later than the previous goal of restarting on May 17. (Reporting by Nora Buli, editing by Terje Solsvik)