NEW YORK - An old map published in 1899 by geographer J. Martin Miller shows that islands in the South China Sea have never been Philippine territory, Zeng Yingjing, the owner of the map, has told Xinhua.

The map was included in a book titled "The Twentieth Century ATLAS and Illustrated World," which was purchased by Zeng, a Chinese-American, at a flea market in New York in 2015.

The map shows the boundary of the US possession in the Philippines agreed by the United States and Spanish Peace Commissioner at the Treaty of Paris in 1898.

The boundaries of the Philippines on the map were marked by a red line, which the South China Sea islands, including the Nansha Islands and the Huangyan Island, clearly lie out of.

Zeng believed that the map is highly credible given its elaborate mapping and detailed introduction to countries around the world.

The map, he said, provides concrete evidence against the Philippines' claim over the South China Sea islands.

"All the islands that the Philippines claims are not within the boundaries that were mapped out in this book. They have no right to say that the South China Sea islands belong to them," Zeng said.

Manila unilaterally initiated an arbitration case against China over maritime disputes in the South China Sea at the Permanent Court of Arbitration in The Hague in early 2013. The decision will probably be announced in May or June.

Chinese officials and experts have defended China's stance of non-acceptance and non-participation in the case, saying the Philippines' unilateral initiation of the arbitration violates international law.