Chinese President Xi Jinping has emphasized the “urgent” need to build a robust navy as he oversaw the country’s largest naval fleet review since 1949, while the government announced live-fire military drills would take place in the Taiwan Strait next week.

Xi headed the fleet review in the South China Sea on Thursday morning, saying the need to build a strong navy “has never been more urgent than today,” according to a Defense Ministry statement. He also urged the navy to stay on high alert, safeguard national interests and strengthen the leadership of the Communist Party.

More than 10,000 service personnel, 48 vessels and 76 aircraft took part in the review, including the Liaoning aircraft carrier, high-tech submarines and warships as well as advanced fighter jets. More than half of the vessels were commissioned after the Communist Party’s National Congress in 2012, when Xi became the party’s general secretary.

The Chinese leader has made the modernization of the Chinese military — especially its navy — a key tenet of achieving what he called “the great rejuvenation of the Chinese nation.”

During a speech at the review, Xi touted progress made toward bolstering the Chinese Navy and said it had “stood up in the East.”

“The party and the people are proud of the PLA Navy,” Xi said, using the acronym for the People’s Liberation Army Navy.

China Central Television (CCTV) also reported Thursday that destroyers involved in the parade were sailing to the Taiwan Strait, where they are to conduct drills. China’s Fujian Maritime Safety Administration announced the same day that the live-fire drills would be held April 18.

Those drills would come weeks after U.S. President Donald Trump signed a law that could elevate the island’s diplomatic status by allowing high-level official visits.

Trump’s signing of the Taiwan Travel Act, which has angered China, encourages visits between the U.S. and Taiwan “at all levels,” specifically citing “Cabinet-level national security officials.” Such exchanges would effectively bolster the diplomatic status of the democratically ruled island, which U.S. officials have avoided since recognizing the government in Beijing under the “one-China” policy in 1979.

China and the U.S. have also in recent weeks squared off over trade and maritime security issues, including the South China Sea.

On Tuesday, Beijing defended its construction of what it called defensive facilities in the disputed South China Sea, calling the deployments “natural rights of sovereign states” and not directed at any specific country, according to a Defense Ministry spokesman.

Beijing claims virtually the entire South China Sea. The Philippines, Vietnam, Malaysia, Taiwan and Brunei all have overlapping claims in the strategic waterway.

The Spratly chain in the South China Sea is home to seven Chinese-held man-made islands that it has fortified with deep-water piers, military-grade airfields, defensive weapons and barracks.

Washington has lambasted Beijing over the man-made islands, which the U.S. fears could be used to restrict free movement in the waterway that includes vital sea lanes through which about $3 trillion in global trade passes each year.

In response, the U.S. has conducted numerous “freedom of navigation operation” (FONOP) patrols in the area.

Collin Koh, a specialist in regional naval affairs at Singapore’s S. Rajaratnam School of International Studies, said that while the United States was likely the primary audience for Thursday’s massive naval show of force, messages were also being sent “omnidirectionally.”

“The drills are also designed to deter other would-be players in the South China Sea, and that includes countries such as Australia and Japan, whose naval presence has been observed more frequently in the area,” said Koh. This included “even the French, and other extra-regional powers such as those in Europe, which had mentioned the South China Sea and raised the prospect of projecting naval presence in the area to safeguard freedom of navigation.”