Citing two sources familiar with the operation, Reuters reported on Tuesday that Russia suspended oil exports via the southern leg of the Druzhba pipeline from early August due to issues relating to transit fees.

"According to the sources, the payment from Russia's pipeline monopoly Transneft to Ukraine's pipeline operator Ukrtransnafta did not go through," Reuters explained.

Market reaction

Crude oil prices rose sharply with the initial reaction to this development. As of writing, the barrel of West Texas Intermediate was trading at $91.85, where it was up 1.55% on a daily basis.