"Similarly, the operations of China's State-owned enterprises, which represent a major part of China's economy, are largely shielded from view by mechanisms such as unpublished government budgets, infrequent WTO notifications and a law that can treat commercial information as state secrets," Wilson said.

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Wang Shouwen, China's assistant minister of commerce, headed a delegation to Geneva with representatives from nine Chinese departments for the review. The WTO members posed more than 1,500 written questions regarding China's economic system and trade policies before the review.

"On the whole, the WTO will give China a more positive evaluation compared with that in the previous reviews," said Tu Xinquan, deputy director of the China Institute for WTO Studies at the University of International Business and Economics.

"China outlined many reforms and opening-up policies in the top-level decision reached in November 2013 at the Third Plenum of the 18th Central Committee of the Communist Party of China. The country is also advancing the new China (Shanghai) Pilot Free Trade Zone as a pilot project to test the further liberalization of trade in services. Those are very positive signals, though the implementation still takes time."

Tu added: "China still has many deficiencies regarding its trade and investment policies, intellectual property rights protection and the opening of services. The challenges will be resolved with the implementation of the reform measures."

China has become the world's largest trader, excluding intra-EU trade. During the period under review, both exports and imports of goods expanded rapidly, with exports totaling $2.21 trillion and imports amounting to $1.95 trillion in 2013, the WTO report noted.