Editor's note: Kong Qingjiang is the dean of the School of International Law under China University of Political Science and Law. The article reflects the author's opinions, and not necessarily the views of CGTN.

A month ago, as part of its response to China's application of its new national security law for the Hong Kong Special Administrative Region (HKSAR), U.S. President Donald Trump signed an executive order to end the special status given to Hong Kong.

As a concrete step, the U.S. Customs and Border Protection (USCBP) issued a notice last week requiring goods made in Hong Kong for export to the United States be labelled as "Made in China" after September 25, 2020, which means that Hong Kong will no longer be entitled to enjoy most-favored-nation (MFN) treatment (such as lower trade tariffs) and a separate customs territory status in its dealings with the U.S. under the United States-Hong Kong Policy Act of 1992.

Some observers even believe that as long as the trade war between China and the United States has not been put to an end, Hong Kong companies will be subject to the same trade tariffs levied on the Chinese mainland's exporters, should they make products subject to these duties.

The U.S. response might be justified under the U.S. law, but its behavior is certainly a violation of the well-established principle of international law — non-interference of the internal affairs of other nations. Moreover, it remains a question whether the U.S. revocation of the status of Hong Kong's separate customs territory and disqualification of Hong Kong products' appellation of origin can sustain the scrutiny of the law of the World Trade Organization (WTO).

Under the WTO law, a member of the organization can be either state or a separate customs territory within the boundary of a particular state. A region within the territory of a state is called a separate customs territory if it possesses full autonomy in the conduct of its external commercial relations. It is just because of its autonomy in the conduct of its external commercial relations that the region is able to join the WTO. In other words, it is not due to the recognition by other members that the region is entitled to a membership in the WTO.

Under the Basic Law of the Hong Kong SAR, Hong Kong enjoys full autonomy in the conduct of its external commercial relations. It is due to this that Hong Kong is treated as a separate customs territory member of the WTO. To put it in another way, Hong Kong's status as a separate customs territory in the WTO is independent of the recognition by the other WTO members.

It should be pointed out that even if a WTO member state genuinely feels a separate customs territory has lost its autonomy in the conduct of its external commercial relations, and is thus no longer entitled to a WTO membership, the member state shall challenge it in a WTO litigation. It is in no position to declare that the separate customs territory ceases to qualify by taking unilateral measures. After all, the WTO is a multilateral trade organization and there provides a built-in dispute settlement mechanism available to members to resolve their differences. Therefore, it is questionable for the United States to unilaterally disqualify the status of Hong Kong in the WTO.

Among such measures entitled under the WTO law, the Hong Kong SAR can challenge the conformity with the WTO law of the U.S. executive order to revoke its special status.

The U.S. requirement that products made in Hong Kong separate customs territory be labeled as "Made in China" cannot sustain the scrutiny of the WTO's Rules of Origin. Apparently, it is certainly not intended to convey a factual message that Hong Kong is part of China, but has the effect of depriving Hong Kong of its entitlement to MFN treatment that any WTO member is entitled under the WTO. For Hong Kong, as a countermeasure, it can also bring the United States to the WTO for its violation of its obligation.

In sum, in order to defend itself and its legitimate rights, bringing the United States to the WTO is a plausible option for Hong Kong.

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