Russia's industrial safety watchdog discovered "thousands" of violations in a national inspection of oil refineries.
The agency has ordered companies to close units at refineries visited by inspectors since last year because of outdated production facilities, Nikolai Kutin, the agency's head, told reporters late last week.
The Ryazan refinery, owned by TNK-BP, the oil producer half-owned by BP, is "in particularly bad shape," he said. "It will require major investment to bring it into normal condition."
TNK-BP has received the results of the inspection and plans to submit a detailed plan to the watchdog, said company spokesman Dmitry Sergeyev.
"TNK-BP is working in close cooperation with the inspection and oversight agencies and is pleased with the objective nature of the inspection," he said.
Russia is seeking to modernize its refineries and will penalize oil companies for failing to upgrade their plants, Prime Minister Vladimir Putin said earlier last month.
The country may see an improvement at refineries in two to three years, Kutin said.