the legal complaint listed rockhopper exploration , premier oil , falkland oil and gas limited and us firms noble energy and edison international .
it also warned the rig 's owner , greece-based firm ocean rig , that it could face ` legal consequences ' over the drilling .
the diplomatic row over the fate of the falklands has worsened in recent weeks , after the uk government pledged to invest £ 180million in the islands ' defences over the next ten years .