Philippine President Ferdinand Marcos Jr. said the presence of a Russian submarine in the Southeast Asian nation’s waters is “very concerning” as its military vowed to continue safeguarding its maritime sovereignty.

President Ferdinand Marcos Jr. said on Monday the presence of a Russian attack submarine in the Philippines' exclusive economic zone in the South China Sea was "very worrisome".

President Ferdinand Marcos Jr. said on Monday the reported presence of a Russian submarine in the Philippine's exclusive economic zone (EEZ) in the South China Sea was "very worrisome". Marcos did not elaborate on the submarine's reported presence,

Philippine President Ferdinand Marcos on Monday described as "very worrisome" the presence of a Russian attack submarine off the country's coast in the disputed South China Sea.

President Bongbong Marcos says the recent sighting of a Russian attack submarine in the West Philippine Sea is "very worrisome."

A Russian attack submarine was recently spotted in Philippine waters in a development which President Ferdinand Marcos Jr. said was “worrisome.”