Almost five million barrels of Russia’s Sokol grade crude should have reached Indian refiners over the past four weeks. 

None of it has got there, with tankers idling miles from their destinations — in one case for more than a month.

It’s unclear what’s holding the vessels up, but US sanctions on tankers hauling Russian crude in breach of a price cap imposed by the Group of Seven nations might be part of the cause.

The US Treasury sanctioned its first two ships tied to the Russian oil trade in mid-October. It followed with another three in mid-November and a further three at the start of December. Six of the eight sanctioned vessels are owned by Russia’s state tanker company Sovcomflot PJSC.

One of the ships on the Treasury list is the NS Century, which was hauling Sokol crude to the Indian port of Vadinar. 

Two days after it was named on Nov. 16 it came to a halt south of Sri Lanka, where it has remained stuck ever since. In the past week, it has been joined by two other Sovcomflot tankers, both are also heading to Vadinar with Sokol crude, according to tanker tracking data compiled by Bloomberg.

It’s not only tankers heading to Vadinar that have come to a stop. Three more should have arrived at the port of Paradip on India’s east coast by now. These too have also stopped short of their destination. 

The Krymsk has been idling about 275 miles from the port since Dec. 4 and has now been joined by the Nellis. A third, the Liteyny Prospect, could join soon them, judging by how far it is from Paradip.

Five of the tankers, each hauling about 700,000 barrels of crude pumped from fields off the east coast of Sakhalin Island in Russia’s Far East, are owned by Sovcomflot. The other, the Nellis, a 16-year-old Very Large Crude Carrier is holding twice as much as each of the other ships. 

Whatever the reason for the holdups, it hasn’t stopped all Sokol crude from heading toward India. Another Sovcomflot-owned tanker completed loading its cargo on Dec. 19 and is heading for Vadinar, where it’s due to arrive on Jan. 5.