Exxon Mobil has been fined $2m for violating sanctions against Russia while US Secretary of State Rex Tillerson was its CEO.
The US Treasury said the oil company had shown “reckless disregard” for sanctions imposed by the Obama administration in 2014 over Russia’s annexation of Crimea.
Exxon’s “senior-most executives” were aware of the sanctions when two of its subsidiaries signed deals with Russian oil magnate Igor Sechin, it added.
Mr Sechin chairs Russian oil giant Rosneft. He is also on a US blacklist that bars Americans from doing business with him.
The Treasury’s Office of Foreign Assets Control (Ofac), said that by engaging with “an official of the government of the Russian Federation contributing to the crisis in Ukraine”, Exxon had caused “significant harm”.
The fine was the maximum civil penalty it could level.
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Exxon has maintained its innocence, saying in a statement that it “followed clear guidance” from the White House and Treasury Department when it did the deals with Rosneft, adding that Rosneft was not subject to sanctions at the time.
It also said it understood that transactions with Mr Sechin in a personal capacity were not covered.
“Based on the enforcement information published today, Ofac is trying to retroactively enforce a new interpretation of an executive order that is inconsistent with the explicit and unambiguous guidance from the White House and Treasury issued before the relevant conduct and still publicly available today,” it said.
“Ofac’s action is fundamentally unfair.”
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But Ofac said there had been several aggravating factors.
Among them were that “Exxon Mobil’s senior-most executives knew of Mr Sechin’ s status … when they dealt in the blocked services of Sechin”.
There was also “significant harm to the Ukraine-related sanctions programme objectives”.
While he was at Exxon, Mr Tillerson opposed the sanctions, saying at the company’s annual meeting in 2014: “We do not support sanctions, generally, because we don’t find them to be effective unless they are very well implemented comprehensibly and that’s a very hard thing to do.”
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Mr Sechin was Mr Tillerson’s main partner as Exxon sought to drill in the Arctic’s Kara Sea, which has vast untapped potential.
Before he became Secretary of State, Mr Tillerson knew both Mr Sechin and Russian President Vladimir Putin for more than a decade.
Since taking office in Washington, Mr Tillerson has taken a tough line on Ukraine-related sanctions.
On a trip to Kiev earlier this month, he said the sanctions would not be lifted until Russia met its obligations.