March 26 (Reuters) - German steel company Thyssenkrupp announced on Thursday that it will extend production cuts at its site in Isbergues in northern France, citing a "ruinous flood of imports" coming to Europe.

The company said production would be shut down completely from June to September, putting 1,200 jobs at risk in Germany and France.

The site has been operating at half capacity since January, the company said, adding that the European market for grain-oriented electrical steel is under severe pressure.

Grain-oriented electrical steel is a key material used in power grids. Imports are not covered by EU plans to cut tariff-free steel import quotas by almost half and impose a 50% duty for excess shipments.

Thyssenkrupp on Thursday said that it is engaged in talks with the European Commission and hopes for the prompt introduction of effective safeguards for workers.

(Reporting by Simon Ferdinand Eibach, editing by Friederike Heine and Thomas Seythal)