Friday will mark the first time U.S. President Joe Biden and Chinese President Xi Jinping have personally spoken since Russia’s invasion of Ukraine, and the call is expected to be tense. The U.S. is convinced that China is preparing to back Russia’s war efforts in Ukraine and Biden is expected not to mince words about the potential fallout of such action, according to multiple news sources. Prior to Russia’s invasion of Ukraine, Vladimir Putin and Xi had signed a joint statement that included damning disapproval of any NATO expansion—Putin’s motivating force for the ruthless invasion. While it is unclear if Xi knew Putin’s full intent against Ukraine, China has not condemned it and, prior to the invasion, discounted the U.S. warning that an invasion was imminent. The two leaders are expected to discuss potential a number of issues, including the potential for U.S. sanctions against China if they back Russia militarily or economically.