China says the Philippines infringed its sovereignty on Wednesday by sending a delegation of politicians to a disputed island in the South China Sea.
Foreign Ministry spokesman Ma Zhaoxu said China had "indisputable sovereignty" over the island, in the Spratlys chain.A group of Philippine congressmen had flown to Pagasa island on Wednesday and declared it Philippine territory.
The Spratly Islands are also claimed by Vietnam and Taiwan.
The Spratly dispute is part of a larger territorial row, which also involves Brunei and Malaysia.
The regional grouping Asean (Association of South East Asian Nations) is currently meeting in Bali, where talks have focused on framing guidelines for resolving the dispute.
Tension has been growing this year, with China making a series of tough statements warning off Vietnam and the Philippines.
"China has indisputable sovereignty over the South China Sea islands and their surrounding waters," said Mr Ma.
"The move of the Philippine side seriously infringed China's territorial sovereignty."
The Philippine congressmen landed on Pagasa island, the only island in the Spratlys populated by Filipinos, and sang the national anthem with residents.
Pagasa, also known as Tithu island, lies about 480km (300 miles) west of the western Philippine province of Palawan.
It has an airstrip, a military base and a small town hall, and is occupied by about 60 civilians.
The Spratly Islands lie in an area thought to be rich in oil and gas. The region also has vital shipping routes.
The step that Philippines took is a brave statement that we are not backing down from any countries if it involves a part of our territory and our rights are being violated. I don't really understand why China is trying to possess the Spratly Islands when it's clearly a part of our territory as far as the picture shows. China is one of the powerful countries in the world and one of our biggest business partners but it doesn't mean that they can easily grab things here and there. I know that I don't have the full knowledge on how they consider a place their own but its common sense that what is near to our country is part of us and China is too far from what they considered as their own. Based on how China is reacting on this issue, I realize that these islands have great economic importance. As what they say there are possible high concentrations of oil deposits on that islands and also a vital shipping route so it is really a clear territorial and economic advantage for countries who are saying that it is theirs. Within this issue also poses a threat between the relationship of the main countries China and Philippines as well as the other countries. It can damage the peace as well as economic ties and the fact that we have many countrymen in their territories as well they bring business opportunities to us, it is really a difficult situation. But we Filipinos must stand together and fight for what we know is ours. We shouldn't let foreigners just step on our toes rather take a stand for our right. Well I just hope that this issue will be settled in a peaceful way and our relationship between these countries will be still the same. We are all part of Asia and we should work together to improve our economies in this time of global financial crisis rather than fight, when in the end all of us will lose.
