UPDATE 1-Groningen gas production to drop 20% faster than planned - gov't

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AMSTERDAM, June 17 (Reuters) - Next year's output at the Groningen natural gas field in the north of the Netherlands looks set to drop 20% more than previously announced, the Dutch government said on Monday.

Production at the field, operated by Royal Dutch Shell and Exxon Mobil, could be limited at 12.8 billion cubic metres (bcm) in the year starting October 2019, the government said, to limit seismic risks in the region.

The government said in February that production would drop to 15.9 billion cubic metres (bcm), but was forced to cap production faster than planned after a 3.4 magnitude earthquake hit the Groningen region last month.

Following that quake, the Dutch gas sector regulator said output should be limited to 12 bcm next year to limit risks. But the government has repeatedly said such a step would lead to shortages, as the Netherlands still depends on Groningen gas for a large part of its energy supply.

Economic Affairs minister Eric Wiebes on Monday said he would ask the regulator to assess the risks of a cut to 12 bcm, as he plans to take a final decision on the production level before Oct. 1.

Output from the field, which once was the largest in Europe, hit a peak of 54 bcm in 2013. Current plans call for ending production at Groningen by 2030. (Reporting by Bart Meijer, editing by Louise Heavens)