Resource constraints and precedent mean China is unlikely to become one of Ukraine's security guarantors - despite Russia's suggestion that it could, according to analysts. With rising expectations for a face-to-face meeting between Russian President Vladimir Putin and his Ukrainian counterpart Volodymyr Zelensky,

The two back-to-back summits that U.S. President Donald Trump hosted over the past week, first with Russian President Vladimir Putin in Alaska and then with Ukrainian President Volodymyr Zelenskyy and other European leaders in Washington,