Production at the Groningen natural gas field could be reduced to less than 12 billion cubic metres per year by October 2020, faster than planned, the Dutch economic affairs minister said in a letter to parliament on Thursday.

Output was projected to drop to below 12 Bcm from its current cap of 21.6 Bcm per year within four to five years under plans announced by Prime Minister Mark Rutte in March aimed at ending production at Groningen by 2030 due to the damaging earthquakes it causes.