BELGRADE, Jan 23 (Reuters) - The U.S. Treasury Department's Office of Foreign Assets Control (OFAC) has extended until February 20 an operating licence for Russian-majority owned NIS NIIS.BEL, Serbia's sole oil refiner, RTS state TV said on Friday.

OFAC imposed sanctions on NIS - in which the majority stake belongs to Russia's Gazprom Neft SIBN.MM and Gazprom GAZP.MM - in October as part of broader measures targeting Russia's energy sector over Moscow's war in Ukraine.