The Philippine government has criticized China for entering Manila's exclusive economic zone in the West Philippine Sea.

The defense ministry said Wednesday that Chinese vessels were found in two separate areas in the South China Sea, some 200 kilometers west of Palawan island.

In a statement released on Wednesday, Department of National Defense Senior Undersecretary Jose Faustino Jr. wrote the country remains open to dialogue.

But the statement goes on to say, "We maintain that activities which violate our sovereignty, sovereign rights and jurisdiction, and undermine the peace and stability of the region, are unacceptable."

The Philippine military says it has confirmed the "swarming" presence of Chinese vessels, over 40 on average, in the waters since September.

The statement was released ahead of President Ferdinand Marcos Jr.'s planned visit to China for summit talks with his Chinese counterpart, Xi Jinping.

A diplomatic dispute ensued between Beijing and Manila last year after more than 200 Chinese vessels were spotted in the South China Sea.

The Philippine government claimed last month that the Chinese coast guard seized suspected rocket debris in the South China Sea.