BEIJING (AP) — China is celebrating the completion of its BeiDou Navigation Satellite System that could rival the U.S. Global Positioning System and significantly boost China’s security and geopolitical clout.

President Xi Jinping, the leader of the ruling Communist Party and the People’s Liberation Army, officially commissioned the system Friday at a ceremony at the Great Hall of the People in Beijing.

That followed a declaration that the 55th and final geostationary satellite in the constellation launched June 23 was operating after having completed all tests.

The satellite is part of the third iteration of the Beidou system known as BDS-3, which began providing navigation services in 2018 to countries taking part in China’s sprawling “Belt and Road” infrastructure initiative along with others.

As well as being a navigation aid with an extremely high degree of accuracy, the system offers short message communication of up to 1,200 Chinese characters and the ability to transmit images.

While China says it seeks cooperation with other satellite navigation systems, Beidou could ultimately compete against GPS, Russia’s GLONASS and the European Union’s Galileo networks. That’s similar to how Chinese mobile phone makers and other producers of technically sophisticated hardware have taken on their foreign rivals.

Among the chief advantages for China is the ability to replace GPS for guiding its missiles, especially important now amid rising tensions with Washington.

It also stands to raise China’s economic and political leverage over nations adopting the system, ensuring that they line up behind China’s position on Taiwan, Tibet the South China Sea and other sensitive matters or risk losing their access.

China’s space program has advanced rapidly since becoming only the third country to fly a crewed mission in 2003 and the country this month launched an orbiter, lander and rover to Mars. If successful, it would make China the only other country besides the U.S. to land on Mars.

China has also constructed an experimental space station and sent a pair of rovers to the surface of the moon. Future plans call for a fully functioning permanent space station and a possible crewed flight to the moon.

The program has suffered some setbacks, including launch failures, and has had limited cooperation with other countries’ space efforts, in part because of U.S. objections to its close connections to the Chinese military.