WASHINGTON--China's first domestically built aircraft carrier is likely to enter into service this year, marking another advance in Beijing's ability to project influence well beyond its shores, the Pentagon said Thursday in an updated assessment of Chinese military power.

The report to Congress comes amid increased emphasis by the Pentagon on adjusting to what it sees as an emerging challenge from China not only in naval strength but also in cyber capabilities, space power and missile technologies.

Last year the Pentagon declared strategic competition with China and Russia to be its top priority, shifting from a focus on fighting extremist groups and insurgencies that began with the invasion of Afghanistan after the Sept. 11, 2001, attacks.

Thursday's report mostly recapped a range of Chinese efforts to strengthen its military.

"Over the coming decades, they are focused on realizing a powerful and prosperous China that is equipped with a 'world-class' military, securing China's status as a great power with the aim of emerging as the pre-eminent power in the Indo-Pacific region," it said.

In predicting that China's first domestically built aircraft carrier will join the fleet this year, the report said the Chinese navy "continues to develop into a global force, gradually extending its operational reach beyond East Asia into a sustained ability to operate at increasingly longer ranges." The carrier began sea trials a year ago.

The only aircraft carrier in China's current naval fleet, the Liaoning, was bought as a mostly empty hull from Ukraine in 2002 and commissioned in 2012. China says aircraft carriers are needed to protect its coastline and trade routes.

State media reports say China is also planning to build a nuclear-powered aircraft carrier capable of remaining at sea for longer periods.

China has the world's largest navy in terms of numbers of ships, although it lags behind the U.S. in technology and combat capabilities.

The U.S. Navy has 11 aircraft carriers, the most of any nation. Earlier this year the Trump administration asked Congress to permit the early retirement of one carrier, the USS Harry S. Truman, but this week President Donald Trump withdrew that request.