The US is allowing a Russian tanker full of crude oil to reach Cuba, the New York Times reported on Sunday, possibly granting a lifeline to the Caribbean island amid a de facto oil blockade imposed by Washington.

Ship tracking data showed the Russian-flagged tanker Anatoly ⁠Kolodkin on Sunday was just off the eastern tip of Cuba.

Anatoly Kolodkin, which departed from Primorsk after loading some 650,000 barrels of Urals crude, could soon discharge at Cuba’s Matanzas port if it does not change its current course, according to tracking services MarineTraffic and LSEG.

Donald Trump has effectively blocked all oil shipments to Cuba in an attempt to pressure the government in Havana. Meanwhile, the US has temporarily lifted sanctions on Russia to help improve the flow of oil that has been restricted by the US and Israeli military strikes on Iran.

The New York Times on Sunday confirmed that the Russian tanker was headed for Cuba, citing a US official who had been briefed on the matter. The Times report said it was unclear why the Trump administration was allowing the shipment to go through. A move by Washington to block the tanker by force, however, could have raised tensions at sea with Russia.

The 650,000 barrels of crude would provide significant relief to Cuba, which, according to President Miguel Díaz-Canel, has not received any oil imports for three months, leading to strict rationing of gasoline and exacerbating an energy crisis that has resulted in multiple power outages across the Caribbean island nation.

When the US military captured Venezuelan leader Nicolas Maduro on 3 January and whisked him back to the US to face drug-trafficking charges, it removed from power a crucial Cuban ally who had been providing oil to Havana on favorable terms.

The Trump administration blocked all Venezuelan oil shipments to Cuba and threatened to impose punitive tariffs on any third country that supplied the Caribbean island, leading Mexico to halt its exports to Cuba.

Another vessel of Russian origin, the Hong Kong-flagged Sea Horse, had been bound for Cuba with 200,000 barrels of fuel, but it was rerouted to Venezuela.