NEW LONDON, Conn. — U.S. National Security Adviser John Bolton told 240 new Coast Guard Academy graduates Wednesday that they will help lead the way in "reasserting American leadership in the Arctic."

"You will help the United States challenge growing Russian military influence in the Arctic, and push back against China's illegitimate claim to 'near-Arctic' status, as well as its use of debt diplomacy against Arctic nations," he said as he delivered the keynote speech at the 138th commencement of the academy in New London, Connecticut.

"And you will provide the search and rescue and disaster response capabilities needed to facilitate greater commerce and scientific research across the High North," he said.

The Trump administration this month warned China and Russia that the U.S. won't stand for aggressive moves in the Arctic region, where warming weather and melting sea ice are rapidly opening the area to development and commerce.

"Soon, with the help of the new Polar Security Cutter," he said, "the Coast Guard will lead the way in reasserting American leadership in the Arctic, which has been neglected for far too long."

The cutter is the first of many icebreakers President Donald Trump plans to introduce to an aging U.S. fleet to enable a year-round U.S. presence in polar regions.

"The United States is an Arctic nation with enduring national interests in that region," he said. "Like our Arctic allies and partners, we want the High North to be a region of low tension, where no country seeks to coerce others through military build-up or economic exploitation. While we encourage commercially driven economic development by the international community, we need to reserve Arctic governance for Arctic nations."

Bolton said the Coast Guard also will play an important role as the Trump administration relentlessly pressures the "Troika of Tyranny" in the western Hemisphere — Cuba, Venezuela and Nicaragua.

The speech also came amid escalating tensions between the U.S. and Iran over unspecified threats the Trump administration says are linked to the Islamic republic. The U.S. sent an aircraft carrier strike group, four bomber aircraft and other assets to the region and is moving a Patriot missile battery to an unnamed country in the area.

Bolton, known for his hawkish stance toward Iran, did not specifically mention Iran during the speech but said Coast Guard cutters are in the Persian Gulf conducting maritime security boardings in U.S. interests. Bolton this month vowed "unrelenting force" in response to any attack by Iran.

A small group of protesters gathered just off the academy grounds before the ceremony and held protest signs criticizing Bolton, including one that said "No War" under a picture of his face.

Several thousand people attended the commencement ceremony, held on the academy's football field with the Coast Guard cutter Sanibel in the background on the Thames River on a warm and sunny day.

The graduates, comprising the largest academy class since 1976, threw their hats in the air as the ceremony neared its end. They are scheduled to report to their new assignments in 30 days.

One of the graduates, Colton Atkinson, of Marietta, Georgia, gave the cadet speech. He urged his classmates to help improve the Coast Guard, which has been criticized for how it has handled sexual harassment and racial discrimination at the academy.

"The ethical treatment of every person is our responsibility," Atkinson said. "As an organization we stand for justice. ... Some of us will go to units where people aren't quite being treated properly, where people are acting immorally. In 30 days, it will be our responsibility to respond. In 30 days, it will be up to us to decide if we will create change in this organization or take the easy way out and turn a blind eye."