On July 12, the Arbitral Tribunal under Annex VII to the United Nations Convention on the Law of the Sea (Unclos) rendered its award on the South China Sea Arbitration. The award expressly ruled that China's claims in the South China Sea, based on its so-called nine-dash line, are contrary to Unclos. The tribunal also decided on the legal status of certain maritime features in the South China Sea and found that no feature in the central part of the South China Sea is entitled to an exclusive economic zone (EEZ) or a continental shelf.

It clearly held that the various activities of China in the South China Sea, such as interference with the activities of the Philippines, large-scale land reclamation and the construction of artificial islands, violate international law.

This arbitration proceeding was initiated by the Philippines in January 2013, against China's claims and activities in the South China Sea. China has denied the jurisdiction of the tribunal to deal with this case, and has completely refused to take part in the proceedings. It has only made its position known through informal means.

However, Annex VII of Unclos, which provides for the procedural rules for the arbitration, expressly states that the absence of a party to the proceedings does not bar its progress. It also stipulates that the award is final and without appeal, and that the parties to the dispute must comply with the award. In other words, as a State party to the Convention, China is legally obliged to comply with the decision.

The South China Sea dispute is a complex one, with a number of countries in dispute with each other, both with respect to sovereignty over islands and maritime areas. We should not expect the award to bring an end to the overall South China Sea dispute.

The territorial dispute over the islands in the South China Sea is outside the scope of the arbitration, and remains unsolved. Quite apart from this issue, however, the maritime aspect of the dispute was complex enough in its own right, due to China's unique claim of historic rights to the waters within the nine-dash line, and also because it was unclear which maritime features in the South China Sea would be entitled to a 200-nautical-mile EEZ and a continental shelf.

The tribunal removed these two uncertain elements from the overall South China Sea dispute by clarifying that the nine-dash line cannot be justified under international law and that no island in the central part of the South China Sea is entitled to a 200-nautical-mile EEZ and a continental shelf.

This resulted in a clear picture in which China is not entitled to make any kind of claim to most of the maritime area of the South China Sea.

The tribunal ruled almost entirely in favour of the Philippines and also found that a number of activities by China were in breach of various provisions of Unclos.

However, as the award itself points out, it is more about building common understandings about entitlement to maritime areas than condemning the unlawful acts by China. Its significance lies in the fact that it addressed the fundamentally different views by the parties of their rights to maritime areas, and indicated what must be commonly accepted in the light of Unclos.

It is indispensable to have such common understandings, if the parties in the South China Sea dispute are to proceed on a path towards its resolution.

In this sense, the award is a major step forward towards the resolution of this entangled dispute. However, this also means that the prospects for the resolution of the dispute will be further diminished if China insists on its one-sided claim and refuses to comply with the award.

The award of the Arbitral Tribunal also has significant implications beyond the South China Sea dispute for the maintenance of the international order at sea.

Ambassador Tommy Koh of Singapore, who presided over the Third United Nations Conference on the Law of the Sea which gave birth to Unclos, referred to this convention as a "Constitution for the oceans".

Worthy of such description, Unclos prescribes the fundamentals of the present maritime order in a manner that balances the rights of coastal states and the navigational rights of other states. Claims to maritime areas not based on the convention may lead to the destruction of that balance, and are a challenge to the international order of the oceans. From this viewpoint, countries should unite to persuade China to comply with the award.

Ever since the Philippines lodged its case, China has been criticising the move as aggravating the dispute in the South China Sea. Recently, China has also begun to claim that many countries actually support its position.

However, such efforts towards justifying non-compliance with the award wholly miss the point. The reason Unclos provides for a compulsory dispute-settlement procedure is to prevent the balance embodied in the convention from being undermined by one-sided interpretation of its provisions.

The use of the mechanism by the Philippines was very much in line with what was intended under the convention. By signing and ratifying Unclos, the parties to the convention have committed themselves to resolve disputes based on international law through the dispute-settlement mechanism.

Even if there is political support from other countries, this cannot justify a departure from the existing legal framework. Whether China complies with the award is directly connected to the question of whether or not it intends to act within the existing legal framework as a responsible global power.

•The writer is Associate Professor at the School of Law, Tohoku University, Japan.