Official archives from Britain and France reveal that legal experts in both nations agreed on the indisputability of China's sovereignty over the Xisha and Nansha Islands, an Irish professor of international law has said.

"The Western concept of the law of territory is really drawn up in a colonial and imperial context where you have different Western countries claiming ownership over islands, which are outside the West," Anthony Carty, author of the book titled "The History and Sovereignty of South China Sea," told Xinhua in a recent interview.

His research delved into the archives of the French and British foreign ministries, spanning the period from the 1880s to the late 1970s. The findings revealed a consensus among legal experts from both countries, indicating that the Xisha and Nansha Islands rightfully belong to China.

According to the expert, the so-called South China Sea arbitration of 2016 is a "chaotic and manipulative use of international law," "a case of double standards," and "a legal trick."

The "legal trick" concerns paragraph 3 in Article 121 of the United Nations Convention on the Law of the Sea (UNCLOS).

This article says an island, "except as provided for in paragraph 3," like other land territory, is eligible to generate maritime rights including the territorial sea, the contiguous zone, the exclusive economic zone, and the continental shelf.

The text of paragraph 3 reads as follows: "Rocks which cannot sustain human habitation or economic life of their own shall have no exclusive economic zone or continental shelf."

Two implications are worth noticing. Firstly, it does not inhibit rocks which can sustain human habitation or economic life of their own from having exclusive economic zone or continental shelf. Secondly, it makes clear that paragraph 3, which is the only exemption provided in this article, is only talking about rocks and not islands, which means it does not apply to islands which cannot sustain human habitation or economic life of their own.

"The tribunal said, well obviously, the South China Sea islands are not rocks, but they were once rocks, and with all the weather and all the sea beating up against the rocks, they have become sand," Carty explained.

"So, the Nansha Archipelago of Islands, being, for the purposes of the Law of the Sea, equivalent to rocks, it does not matter to which States they belong, concludes the Tribunal. This reasoning of the Tribunal is a trick," he continued.

"It is manifestly unprofessional, abusive, and politically motivated twisting of the clear - if very badly drafted - terms of the article of the convention. For that reason the decision of the tribunal can and should be disregarded," he added.

The law professor pointed out that Washington has been attempting to maintain hegemony and destabilize the Asia-Pacific region by manipulating its regional allies to provoke China in the South China Sea.

"It is very clear that the Americans have decided that the Western Pacific is a part of the world that they have to be able to control. And they have to be the dominant power in that area. And that is the issue at the moment. So legal issues are really a matter of secondary importance. And they're very clear about that," he said.

"There is huge cynicism with which Washington in 1956 considered the expediency of encouraging the Filipinos to make claims to the islands, despite the fact the French and the British are very clear about the fact that there is no credible Filipino claim to any territories in the South China Sea and despite the fact that the U.S. itself did not consider the Philippines had any claim," Carty said.

"Washington is creating chaos for the sake of it in order to promote and ferment disagreements and differences in the area, which they can then use to weaken China. It seems to be quite clear, and they are quite explicit about it," he added.