Munich — U.S. Secretary of Defense Mark Esper told world leaders and security experts Saturday that China is the Pentagon's "top concern." He said it is urgent that the international community wakes up to the dangers posed by the country.

"It is essential that we — as an international community — wake up to the challenges presented by China's manipulation of the long-standing international, rules-based order that has benefited all of us for many decades," he said at the Munich Security Conference.

Esper emphasized the U.S. doesn't want a conflict with Beijing and that the world is too interconnected for that. But he criticized China's aggressive economic policy and its military expansion.

Get Breaking News Delivered to Your Inbox

Under President Xi Jinping, the country is moving further in the wrong direction, he said.

U.S. government representatives on the sidelines of the security conference warned German officials on Friday against the use of technology originating from Chinese communications firm Huawei and the manufacturer ZTE. Lawmakers in Washington have repeatedly accused Huawei of being a threat to U.S. national security, and of using its equipment to carry out espionage on behalf of the Chinese government.

Speaking Saturday, U.S. Secretary of State Mike Pompeo called the tech giant and other Chinese state-backed tech companies "Trojan horses for Chinese intelligence."

His concerns about Huawei were echoed by Esper, who said reliance on Chinese 5G vendors could "jeopardize our communication and intelligence sharing capabilities, and by extension, it could jeopardize our alliances."

The focus of the annual gathering, which is taking place over three days, is the decline of Western influence amid rising threats from China and Russia.

Pompeo, who joined onstage Saturday by NATO chief Jens Stoltenberg, opposed the pessimistic notion of the conference.

He rejected a claim made by some European leaders that transatlantic relations are deteriorating. "The West is winning, we are winning together," he said.

Pompeo's remarks were to some extent aimed at German President Frank-Walter Steinmeier, who during his opening speech on Friday accused the U.S. of straining the transatlantic bond and, with Trump's "America First" policy, "rejecting the concept of the International community."

Pompeo announced that the U.S. will support the "Three Seas Initiative" with $1 billion. The initiative provides for closer cooperation between twelve central and Eastern European countries bordering the Baltic, Black and Mediterranean seas.

He also said the U.S. will not withdraw from Europe, referring to the American billion-dollar investment to protect NATO's eastern flank and the major Defender 20 maneuver, the largest U.S. troop deployment in Europe in more than a quarter of a century.