Increasingly isolated by the West over Ukraine, Russian President Vladimir Putin will hope for a sympathetic ear on a visit next week to China, which is also being more assertive in its territorial disputes with smaller neighbors.

Chinese President Xi Jinping has made a big public show of underscoring the importance of ties with Russia, and Moscow was the first capital he visited after assuming the presidency last year. Xi also attended the Winter Olympics in Sochi at Putin's invitation.

But, while the two see eye to eye on many international diplomatic issues, including the conflict in Syria, and generally vote as one on the United Nations Security Council, China has not proved so willing to support Russia on Ukraine.