The Swiss Supreme Court in Lausanne ordered the Israeli firm, the Trans-Asiatic Oil Ltd., or TAO, to pay the money to the National Iranian Oil Company (NIOC), the website of Israeli daily Haaretz reported on Monday.
According to the Swiss court, sanctions have been lifted against the NIOC, and there is now no legal obstacle in the way of transferring the long-overdue payment.
The Israeli firm also has to pay roughly $200,000 in court costs.
TAO had been involved in a partnership with the National Iranian Oil Company under Iran’s last monarch, Mohammad Reza Pahlavi, who was deposed in the 1979 Islamic Revolution. The Israeli firm operated a fleet of tanker ships to carry Iranian oil to European customers.
The partnership ended in 1979, but the Israeli firm refused to pay for the Iranian oil already sold to third parties.
The Islamic Republic, which does not recognize the Israeli regime, launched the arbitration process to obtain the money for the oil that had been supplied on credit under the deposed Iranian monarch.
The total sum in dispute is estimated at some $7bn.
The court in Switzerland had ruled in 2015 that Israel pay Iran the money, but the Tel Aviv regime had appealed.
A series of sanctions against Iranian firms and individuals has been lifted under a nuclear deal Iran signed with six world powers in 2015.