The German sawmiller posted a statement on its website saying it had been left with no choice but to further its legal efforts after being left at a considerable economic disadvantage by the log contract issues.
Klausner said despite a recent court decision backing its original contract agreements with NRW, the state had entered into new supply commitments with other sawmills that prevented fulfilment of its own contractual claims.
"We have to defend ourselves, even if we regret it very much," Klausner said.
Klausner said it had sought dialogue with NRW, "unfortunately without success" and that solutions had been "blocked".
The company said NRW was being disingenuous about the cause of the breach of contract.
"Our request for a preliminary injunction is not directed against the sawmill industry," it added.
Klausner is claiming compensation of €56m in relation to the contract breach and closure of its Adelebsen sawmill.
