Five Chinese warships were monitored within Philippine territory in southern Philippines since last month, a military commander said on Wednesday.

"About the incursion of Chinese warships in the Philippine territory particularly in Sibutu Strait, we have (monitored) two last July, three this August," said Lt. Gen. Cirilito Sobejana, Armed Forces of the Philipines (AFP) Western Mindanao Command chief, Wednesday.

Sobejana said this was reported to the AFP.

"I forgot (the date) but I already have ( sent) a special report to the higher headquarters about that," he said.

Sobejana said the monitored presence of the Chinese warships is not considered as innocent passage.

"They are not hostile, but it was not a innocent passage because (if it is) innocent passage (they should sail only on a) straight line. If they made a curve, that is no longer considered as innocent passage," he said.

"Innocent passage follows the sea lanes of communications, straight line. Since these are warships, their entry to our territory should be coordinated so we informed the national leadership so that they can engage with their counterparts on the Department of Foreign Affairs or the attaches there in Manila," he added.

Sobejana said the passage of the Chinese warships were monitored through coastal patrol operation of the naval and aerial assets of the AFP.

"We have coastal patrol, our small aircraft and naval assets...since they saw our presence, they immediately left the territory of our country," he said. Robina Asido/DMS