US State Department on Wednesday confirmed that a senior United States official personally offered several millions of dollars to the Indian captain of the Iranian tanker suspected to be transporting oil to Syria.

Financial Times reported that Brian Hook, the State Department point man on Iran sent e-mails to captain Akhilesh Kumar in which he offered ‘good news’ of millions in US cash to live comfortably if he steered the Adrian Darya 1 to a country where it could be seized.

“We have seen the Financial Times article and can confirm that the details are accurate. We have conducted extensive outreach to several ship captains as well as shipping companies warning them of the consequences of providing support to a foreign terrorist organization,” a State Department spokesman said, referring to Iran’s elite Revolutionary Guards.

The Adrian Darya 1 was held for six weeks by the British overseas territory of Gibraltar on suspicion that it was delivering oil from Iran to its main Arab ally, Syria in violation of European Union sanctions on President Bashar al-Assad’s regime.

Despite the pressure from the US, Gibraltar released the ship, formerly called  Grace 1 on August 18 after receiving written assurances that the vessel would not head to countries sanctioned by the EU.

The Adrian Daya 1 has been elusive since sailing off from Gibraltar, with monitors reporting that it has been moving in the eastern Mediterranean near Lebanon.

Iran’s Foreign Minister, Mohammad Javad Zarif has however mocked Hook’s initiative, tweeting: “Having failed at piracy, the US resorts to outright blackmail – deliver us Iran’s oil and receive several million dollars or be sanctioned yourself.”

US authorities said the 43-year-old Kumar took over as captain in Gibraltar. After he apparently did not respond to the US offer, the Treasury Department on Friday imposed sanctions on the ship and on Kumar himself, freezing any assets he may have in the US and criminalizing any US financial transactions with him.

The US also announced on Wednesday that it was imposing sanctions on a shipping network alleged to be tied to the Revolutionary Guards and offering up to $15 million for information that could disrupt the unit’s finances.