As its name suggests, PetroChina Company Ltd is the listed arm of state-owned China National Petroleum Corporation (CNPC). It is China's biggest oil producer, and is listed in Hong Kong, New York, and Shanghai.

Pumping gear and a gas derrick in Urengoy, Siberia. Photo: Bloomberg

PetroChina eyes US$10b stake in Russian gas fields

PetroChina is seeking to invest in Russian gas fields as part of efforts by China and Russia to conclude gas-supply negotiations that have dragged on for almost a decade, four people with knowledge of the matter said.