The case has strained relations between Athens and Tehran amid rising tensions between Iran and the United States.
The removal of oil from Lana, formerly Pegas, prompted Iranian forces to seize two unidentified Greek tankers in the Middle East Gulf.
“The (Greek) Supreme Court’s ruling … favors Iran,” said a Greek government official, who asked not to be named because of the sensitivity of the issue. The decision, which was not made public, came to the notice of the government on Tuesday, the official said.
Another official confirmed the verdict. A government spokesman said the government would not comment on court rulings.
More than two months later, the Iranian-flagged Lana was arrested near the town of Krystos, off the coast of the Greek island of Evia.
Greek authorities approved its release earlier this month after a court ruled in favor of the Iranian company and overturned an earlier court order.
Greek media reported that the United States has appealed the decision to the Greek Supreme Court.
US government officials had no immediate comment.
Some of the ship’s cargo of Iranian oil was transferred to another US-leased ship, the Ice Energy, docked at the port of Piraeus.
“The Lana is expected to receive fuel and test its engine later today, so it can begin oil exchange and sail by the end of the week,” the first official told Reuters.
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