Payment issues linked to U.S. sanctions on Russia were behind the latest halt in oil supplies by Russia to the Czech Republic via the Druzhba pipeline, two sources familiar with the matter told Reuters.

The Czech state company that operates the country's oil pipeline network says deliveries from Russia through the Druhzba pipeline have been halted.

Druzhba is the largest Russian oil pipeline supplying crude to Europe. Built in the 1960s, it splits in the Belarusian city of Mazyr into northern and southern branches. The northern route runs through Belarus, Poland, Germany, Latvia, and Lithuania, while the southern branch extends through Ukraine, the Czech Republic, Slovakia, and Hungary.

Oil flow through the "Druzhba" pipeline to the Czech Republic has ceased, posing a challenge for Orlen Unipetrol. On Wednesday, the Czech government decided to lend the company up to 364,000 tonnes of crude oil from its strategic reserves if the supply interruption continues.