HONG KONG -- The Permanent Court of Arbitration (PCA) in The Hague has no jurisdiction over South China Sea disputes between China and the Philippines, which unilaterally filed an arbitration case, a Hong Kong law expert said on Monday.

Teresa Cheng, Chair of the Hong Kong International Arbitration Center (HKIAC) made the remarks during a media briefing, citing the United Nations Convention on the Law of the Sea (UNCLOS).

Cheng said that according to the UNCLOS, both sides in the disputes should conduct negotiations prior to filing an arbitration, while the Philippines has not conducted negotiations with China.

China and the ASEAN member states, including the Philippines, jointly signed the Declaration on the Conduct of Parties in the South China Sea (DOC), agreeing to solve disputes by peaceful means.

"The DOC is still under implementation, therefore both the Philippines and China do not have the right to file an arbitration during this process," Cheng said, "From legal aspect, the PCA has no arbitration jurisdiction over the case as the Philippines did not take the right steps."

In addition, the sovereignty and territorial disputes are not under the jurisdiction of the UNCLOS, Cheng said, adding China has made related declaration excluding disputes concerning the above issues.

Cheng also said a conference under the title of "Public International Law Colloquium on Maritime Disputes Settlement" will take place in Hong Kong on Friday and Saturday.

The colloquium, co-hosted by the HKIAC and the Chinese Society of International Law (CSIL), aims to provide a unique platform for scholars and practitioners from all over the world to share views mainly on territorial sovereignty and maritime delimitation, the disputes settlement mechanism under the UNCLOS, Cheng said.

The PCA will publish the award of the arbitration on Tuesday. In reaction to the award, the colloquium will provide a special session dedicated to discussion and comments on the topic from a legal perspective, Cheng said.