This satellite image shows the Yongshu Jiao of China's Nansha Islands. [Photo/Xinhua]

Russia opposes actions "internationalizing the South China Sea issue" and favors direct negotiation between the countries involved, as China aims to uphold "the authority of the law" by rejecting unilateral arbitration.

The show of support came as a tribunal at the Permanent Court of Arbitration in The Hague prepares to issue a ruling, expected in late May or early June, in Manila's sovereignty case against China. The tribunal was established in 2014 at Manila's request, and China has rejected the arbitration process since the request was filed.

Russian Foreign Minister Sergey Lavrov, while meeting with his Chinese counterpart Wang Yi in Moscow on Monday, said Moscow supports direct negotiation by countries directly involved to resolve disputes.

According to a Foreign Ministry media release on Tuesday, Wang told Lavrov that Beijing's rejection of the Philippines' unilaterally proposed arbitration case is a move meant to "uphold the dignity and authority of the law".

"Both China and Russia should remain alert against behavior abusing the mechanism of compulsory arbitration," said Wang, who visited Moscow to attend the 14th meeting of foreign ministers of China, Russia and India.

On Monday, Wang said China is "entitled to choose by itself, in accordance with relevant laws, ways for resolving disputes".

Reuters noted that the court has no powers of enforcement and its rulings have been ignored before.

Wu Shicun, president of the National Institute for South China Sea Studies, said that the tribunal "has triggered concerns over it assertively expanding its realm of jurisdiction as well as its impartiality".

Wu said the Philippines and Western supporters, including the United States, are attempting to force China into a corner, and the disputes "will not be resolved by the arbitration, but will flare up and worsen".