WASHINGTON -- South Korean President Yoon Suk Yeol vowed Thursday to work together with the United States to promote freedom around the world, saying the country will play a role as a "compass for freedom."

Yoon made the pledge during an address to a joint meeting of the US Congress, as he recalled the birth of the bilateral alliance 70 years ago at the end of the Korean War and looked forward to a new chapter of closer cooperation.

"Our alliance was forged 70 years ago to defend Korea's freedom," he said in English. "The alliance has now become a global alliance that safeguards freedom and peace around the world."

Yoon said South Korea will fulfill its responsibilities and play a part that matches its economic capacity.

"Together with the US, Korea will play the role as a 'compass for freedom,'" he said. "It will safeguard and broaden the freedom of citizens of the world."

Yoon spoke on the fourth day of his six-day state visit to the US, which came as the two countries celebrate the 70th anniversary of their alliance. On Wednesday, Yoon held a summit with US President Joe Biden at the White House and attended a state dinner.

During his speech, Yoon put a spotlight on the Americans who helped defend South Korea in the Korean War, including the late Colonel William Weber, who lost his right arm and leg in the Battle for Hill 324 in Wonju.

Yoon asked a granddaughter of Weber to stand up from the audience and thanked her on behalf of the Korean people.

"Korea will never forget the great American heroes who fought with us to defend freedom," he said.

Paying tribute to all the Korean War veterans and their families, he added: "You did not hesitate to send your sons and daughters, husbands and wives, brothers and sisters. You answered the call to defend the freedom of a country across the Pacific."

Yoon recalled that there was no guarantee of success when the alliance started, but now it is stronger than ever, more prosperous together, and more connected like no other.

"Indeed, it has been the linchpin safeguarding our freedom, peace and prosperity," he said.

Yoon also used the speech to highlight challenges to democracy, saying false propaganda and disinformation are distorting the truth and public opinion in many parts of the world.

"We must not be fooled by such deception and disguise," he said. "We must work together and fight the forces of falsehood and deception that seek to destroy democracy and the rule of law."

Claiming that freedom and democracy are once again under threat, Yoon denounced the war against Ukraine as a violation of international law.

"It is an attempt to unilaterally change the status quo with force," he said. "Korea strongly condemns the unprovoked armed attack against Ukraine."

On Ukraine, Yoon said South Korea will stand in solidarity with the free world, actively work to safeguard the freedom of the Ukrainian people and support the country's reconstruction.

On North Korea, Yoon noted that he and Biden agreed Wednesday to strengthen the US nuclear commitment to South Korea.

"Along with close Korea-US coordination, we need to speed up Korea-US-Japan trilateral security cooperation to counter increasing North Korean nuclear threats," he said.

"My government will respond firmly to provocations," he continued, describing the North's nuclear program and missile provocations as a serious threat to peace on the Korean Peninsula and beyond.

"But at the same time, we will keep the door open for dialogue on North Korea's denuclearization," he said, urging North Korea to cease its provocations and take the right path.

Yoon also called attention to North Korea's human rights abuses, referring to cases of people being shot and killed for violating COVID-19 prevention measures and some being publicly executed for watching and sharing South Korean shows.

"We must raise global awareness of the dire human rights situation in North Korea," he said. "We must not shy away from our duty to promote freedom for North Koreans."

Yoon was the seventh South Korean president to address a joint session of Congress and the first since President Park Geun-hye in 2013. Park also spoke in English at the time.

His speech was received with frequent applause and standing ovations. At times, he prompted laughter from the crowd

"Even if you didn't know my name, you may know BTS and BLACKPINK," Yoon said, referring to two popular K-pop bands. "BTS beat me to the White House, but I beat them to Capitol Hill."

BTS visited the White House last May to meet with Biden and speak out against anti-Asian hate crimes. (Yonhap)