It's unclear what prevented the crude deliveries from reaching India, but now the tankers are idling at sea miles off their destinations.

Roughly five million barrels of Russian oil that was on the way to India never reached their destination, according to a Bloomberg report.

The cargoes of Russia’s Sokol grade crude were supposed to arrive over the past four weeks, but instead the relevant tankers are idling at sea, miles out from their intended ports.

It’s unclear why the ships haven’t arrived, per the report, but sanctions on sellers moving Russian crude above the $60 price cap set by G7 nations may be part of the explanation.

The US Treasury has sanctioned eight ships tied to the crude cargoes since October, with six of them owned by Russia’s Sovcomflot PJSC.