Iraq has filed a case against Greek shipping company Marine Management Services (MMS) for its role in the “illegal” export of crude from the autonomous Kurdistan region, the oil ministry in Baghdad said in a statement on Thursday.

The statement said MMS operated five vessels that had transported crude oil on behalf of the Kurdistan Regional Government (KRG) from the Mediterranean port of Ceyhan, ignoring warnings from Baghdad.

“MMS is liable for damages of at least $318 million, and possibly significantly more, as a result of its willing and active participation in the KRG’s illegal crude oil export scheme,” the statement read.