Russian-Chinese relations remain strong -- expert / Putin-Xi meetings always give special boost to Russia-China relations, Lavrov says / Russian-Chinese relations not aimed against third countries -- top Chinese diplomat / Leaders' dialogue ensures development of Russia-China relations -- ambassador / Russia-China foreign policy ties stabilize world affairs -- Putin / Russia-China relations serve as model for others in modern world, Putin says / Chinese-Russian relations withstand all tests, continue developing -- Chinese ambassador / West fails to vilify China-Russia relations -- expert / Seasoned China-Russia ties ensure global stability -- Chinese expert / Russia-China friendship undermining West's world order -- European Commission chief