Report notes that some government mechanisms aren't always transparent

The World Trade Organization is conducting a three-day trade policy review of China ending on Thursday as the country has grown into the world's largest goods trader over the past two years and now pledges further opening of its domestic market into the world economy.

In a 200-page report prepared by the WTO Secretariat, the world's top trade body evaluated such things as China's trade and investment policies, tariffs, trade remedies and government procurement from the second to the first half of 2014.

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The review is the fifth one after China's accession into the WTO in December 2001. China is subject to the review every two years.

The WTO found that China's trade and investment policy is managed and fine-tuned through a number of legal instruments. China has continued its efforts to facilitate trade, which date back to 2006, by launching a series of reforms, including the introduction of paperless customs clearance procedures. In its quest to attract foreign direct investment, China has taken measures aimed at simplifying rules and easing restrictions on the use of capital for direct investments.

The report also found that trade and investment policies are not always clear, as they sometimes overlap and even conflict, reflecting different agendas at the different levels. The layers of regulation add another level of difficulty when trying to unravel specific policy measures in China. Customs procedures around the country still require harmonization. The updated notifications appear to be necessary in the area of subsidies.

The United States Trade Representative's Deputy Chief of Mission Chris Wilson said during the Tuesday review that many aspects of China's trade and investment policies and practices seem to be hidden away in unpublished measures, internal instructions, oral directives and confidential documents - or for some other reason are simply unavailable.