BERLIN- Work to complete the subsea Nord Stream 2 gas pipeline can go ahead in German waters, Germany's federal maritime regulator BSH said on Monday.

Two environmental groups had in January filed complaints with BSH against a move to expand the period during which construction work could theoretically take place, effectively preventing further work on the pipeline.

(Reporting by Maria Sheahan Editing by Riham Alkousaa) ((maria.sheahan@thomsonreuters.com; +49 30 22013 3680;))