Naval troops with the Chinese People’s Liberation Army march in Tiananmen Square during a military parade marking the 70th anniversary of the end of World War II Thursday in Beijing. (Damir Sagolj/Reuters)

On the last day of President Obama’s visit to Alaska, the U.S. military observed five Chinese warships plying the waters of the Bering Sea for the first time, but Pentagon officials said Thursday the foray was no cause for alarm.

“This is the first time we have observed [Chinese navy] ships in the Bering Sea,” said Cmdr. Bill Urban, a Pentagon spokesman. “We respect the freedom of all nations to operate military vessels in international waters in accordance with international law.”

The Chinese foray Wednesday in the frigid sea between Russia and Alaska came after the vessels participated in a naval exercise with Russia. At a military parade Thursday in Beijing marking the end of World War II, Chinese President Xi Jinping announced a reduction in the size of the country’s armed forces as part of moves to modernize the military and shift resources from ground forces to the Chinese navy and air force.

The Pentagon identified the Chinese vessels in the Bering Sea as three surface combatant ships, one amphibious ship and one supply ship.

Although Obama was traveling in northern Alaska near the Arctic Circle at the time, White House press secretary Josh Earnest said the Defense Department had “not detected any sort of threat or threatening activities.”

Speaking aboard Air Force One as Obama flew near the Bering Sea, Earnest said the intent of the Chinese deployment was “still unclear.”

China has increased its defense spending in an effort to build a “blue-water” ocean-going navy that can project power far from its shores.

The Chinese buildup is regarded as threatening by other countries in the region, notably those that claim disputed islands in the South China Sea. Beijing has moved aggressively to develop a presence on and around the islands and keep other nations’ naval vessels and fishing fleets away.

But in his speech at Thursday’s military parade, Xi sought to allay regional fears of China’s growing power, pledging that his country “will never seek hegemony” and “will never seek to expand.”

Xi is preparing to make a high-profile state visit to the United States later this month.

According to Dean Cheng, a China expert at the Heritage Foundation think tank in Washington, the foray into the Bering Sea was designed to send a message to Washington, Reuters news agency reported.

Chinese salute from a bus during a military parade at Tiananmen Square to mark the 70th anniversary of Japan's surrender during World War II in Beijing, Thursday, Sept. 3, 2015. (Wang Zhao/AP)

“It is living up to what the Chinese have been saying, ‘We are now a blue-water navy. We will operate in the far seas, and we are a global presence,’ ” Cheng said.

Missy Ryan contributed to this report.

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