The presence of a Russian submarine in the Philippines exclusive economic zone in the South China Sea is "very worrying", said Ferdinand Marcos Jr. on Monday.

"That is very worrying." Marcos said that any intrusion in the West Philippine Sea or our EEZ is very concerning.

In a statement released on Monday by Navy spokesperson Roy Vincent Trinidad, a Russian Kilo class submarine was sighted at 80 nautical miles from the province of Occidental Mindoro in the west. This confirms a report published by the Philippine Daily Inquirer.

The Philippine Navy frigate Jose Rizal made radio contact with a Russian submarine that confirmed its identity and intent as UFA 490.

Trinidad did not elaborate on the reason for its presence in the area. "The Russian ship stated that it was waiting for improved weather conditions to proceed to Vladivostok (Russia)."

He added that the Philippine Navy escorted this submarine to ensure compliance with maritime laws.

The Russian embassy in Manila was not immediately available for comment.

The Russian Kilo-class subs are among the quietest and have been continuously refined since the 1980s.

In 2022, when Russian President Vladimir Putin was in Beijing just a few days before Moscow invaded Ukraine, the two countries declared a partnership with "no boundaries". In July, the two countries conducted live-fire exercises in South China Sea.

The overlapping claims of Manila and Beijing in the South China Sea have escalated tensions over the last year. Beijing has rejected a 2016 decision by an arbitral tribunal that China's historic claims to the disputed watersway were without basis. (Reporting and editing by John Mair, Stephen Coates, and Mikhail Flores)

(source: Reuters)