The Federal Anti-Monopoly Service said Wednesday that it would get involved in a feud between Rosneft and Gazprom over access to the gas giant’s pipeline network.

The watchdog opened a case after Rosneft filed a complaint alleging that Gazprom limited Rosneft’s access to the country’s main gas pipeline network from April to August.

Because it was unable to sell the gas, Rosneft said it had to flare off associated gas in quantities exceeding the maximum amount permitted by environment legislation, thus incurring a fine.

Gazprom controls the country’s gas transmission network — the main system of pipelines used to transport gas throughout the country. Rosneft has to use the system to transport the gas that it obtains as part of the oil drilling process from its oil fields in eastern Siberia.The case will be considered on Dec. 2.