(CNN) -- China's President Xi Jinping will have plenty to discuss with his Russian host and counterpart Vladimir Putin when they meet on the sidelines of the G-20 leaders' summit in St. Petersburg this week, as relations between the former foes grow cozier. The hot issue is clearly Syria, where China and Russia strongly oppose any U.S.-led military intervention against President Bashar al-Assad's government in Damascus over its apparent use of chemical weapons. Both urge restraint and call for a political solution -- much to Washington's consternation. Xi, who calls the Sino-Russian relationship the "best" among major countries, says they will always be good neighbors who aspire to "never be enemies." China is a major buyer of Russian weaponry and the two countries held their biggest joint naval exercise in the Sea of Japan in July this year.
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China and Russia have signed energy deals, conducted joint naval exercises
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Presidents Xi Jinping and Vladimir Putin have hailed Sino-Russian relations
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Both countries are opposed to military intervention in Syria
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Relations between China, Russia and Washington have been strained in recent months
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While China is @placeholder's biggest source of manufactured goods, it is Russia that supplies most of the military equipment used by the Syrian armed forces and has been its most steadfast ally.
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When Xi officially became China's president in March this year, his first overseas trip was to @placeholder.
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Even today, with energy sales to China being such a key contributor to @placeholder's national budget, there is always the potential for friction.
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When it comes to @placeholder-U.S. relations, Xi so far has shown an outgoing style in pursuing what he calls the great Chinese dream of national renewal.