China's leader Xi Jinping has attended a massive naval display in the disputed South China Sea.
Speaking from an undisclosed location, Mr Xi said the need for a strong navy had "never been more pressing".
More than 10,000 naval personnel, 76 fighter jets and a flotilla of 48 ships and submarines took part in the drill.
Several nations claim parts of the resource-rich South China Sea, but recent years have seen Beijing reasserting its claim.
The naval display, described by Chinese media as the largest of its kind, came ahead of planned live-fire military drills by China in the narrow strait separating it from Taiwan on 18 April.
Footage broadcast on Chinese state TV showed the leader addressing forces aboard a navy destroyer before watching jets take off from the country's sole aircraft carrier.
Beijing has the world's largest standing army and has sought to expand its naval power in recent years, consistently increasing defence expenditure.
But tension remains over parts of the South China Sea involving a number of countries, including China, Vietnam and the Philippines.
As part of its territorial claims, China has been involved in island-building. Meanwhile the US has sent military vessels and aircraft to the region in what it describes as "freedom of navigation operations".