China and Russia have long publicly celebrated their relationship as a way to counterbalance the U.S. and achieve what they describe as a multipolar world. But mistrust stretching back decades has hampered ties between the bordering nations.
Russia is eager to tap growing Chinese demand for natural gas, particularly as demand from some of its European buyers has waned in recent years. China wants to use more of the cleaner-burning fuel as a way to curb severe air pollution that afflicts many of its cities.