The United States has unsealed a warrant outlining vast violations of sanctions against Iran in a last-ditch attempt to seize an Iranian oil tanker carrying 2.1 million barrels of oil at the heart of growing tensions between Iran and the West, according to Reuters. The Grace 1 was seized by British Royal Marines off Gibraltar on July 4, which led to Iran seizing a British oil tanker in mid July in a move they called “reciprocal.” On Thursday, a Gibraltar court ordered the ship to be released despite attempts to keep it detained by the United States, which believes the oil is destined for Syria and connected to Iran’s Islamic Revolutionary Guard Corps. The warrant also calls for the seizure of nearly $1 million from a U.S. bank tied to the Iranian Paradise Global Trading LLC company. The U.S. State Department did not respond to a request by Reuters for clarification about how the warrant could be enforced. The Grace 1, while free to leave Gibraltar, has had difficulty securing a new crew to leave the port, but is expected to set sail Sunday.