Iraq filed suit on Monday in a Texas court to gain control of a cargo of crude oil from Iraqi Kurdistan that Baghdad says was sold without its permission.
The United Kalavrvta tanker, carrying some 1 million barrels of crude worth about $100 million, arrived off the coast of Texas on Saturday but has yet to unload its disputed cargo.
The ship, which is too large to enter the port of Galveston near Houston, was given clearance by the U.S. Coast Guard on Sunday to transfer its cargo offshore to smaller boats that would deliver it to the U.S. mainland.
Iraq, in its filing in U.S. District Court for the Southern District of Texas, asked for an order allowing the cargo to be seized by the U.S. Marshals Service.
Sale of Kurdish crude oil to a U.S. refinery would infuriate Baghdad, which sees such deals as smuggling.
The U.S. State Department has expressed fears that independent oil sales from Kurdistan could contribute to the breakup of Iraq, said the oil belongs to all Iraqis, and warned potential buyers of legal risks.
But it has also made clear it will not intervene in a commercial transaction.
Copyright Reuters 2014.