Former Secretary of State Mike Pompeo joined the chorus of senior international figures mourning the loss of Shinzo Abe, the former Japanese Prime Minister who was assassinated Thursday by a lone gunman. 

In an interview with Fox News Digital, Pompeo called Abe "the perfect partner for the United States."

Pompeo had known Abe since Pompeo's time in Congress and told Fox News Digital, "It's both heartbreaking and dangerous to have a leader, a world leader, assassinated while he is out making his case to the people of Japan. He's out campaigning. He was exercising his political rights. It's something that we all ought to be mindful of in terms of political violence."

Abe was assassinated while campaigning in the Nara prefecture for his center-right Liberal Democratic Party ahead of Sunday's election for the country's upper house of parliament.

FORMER JAPANESE PRIME MINISTER SHINZO ABE ASSASSINATED DURING CAMPAIGN SPEECH, HOSPITAL OFFICIALS CONFIRM

Abe Shooting

In this image from a video, a man, center, is detained near the site of gunshots in Nara, western Japan. Japan's former Prime Minister Shinzo Abe was shot and died later after giving a campaign speech in Nara.  (Kyodo News via AP)

Pompeo described his relationship with the late Japanese leader. 

"As for me, I got to know him pretty well," Pompeo said. "I met him first when I was a member of Congress back in 2015 when he spoke to the joint session. And then, of course, got to know him better when I was CIA director."

Pompeo noted that, as Secretary of State, he found Abe to be candid. "He was always straight up, 'Mike, here's what we're working on, here's what we need, here are the things we can do to help you,'" Pompeo recalled.

Japanese Prime Minister Shinzo Abe

Japanese Prime Minister Shinzo Abe, leader of the Liberal Democratic Party, answers questions from a reporter during a TV interview in Tokyo Oct. 22, 2017. (AP)

Pompeo, who served as President Trump's secretary of state for three years, described Abe's importance to the U.S. in combating China.

"He was the perfect partner for the United States as we began to both work on our economies together and deliver the deterrence that we're going to need to keep the Chinese Communist Party at bay," Pompeo explained. "I will miss him. the world, most importantly, will miss him."

TRUMP MOURNS JAPAN'S SHINZO ABE, 'A UNIFIER LIKE NO OTHER' WHO' CHERISHED HIS MAGNIFICENT COUNTRY'

Abe was a strong believer in the power of a U.S.-Japan friendship and spent his career hosting, wooing and negotiating with American statesmen.

Speaking earlier Friday to Bill Hemmer on America's Newsroom, Pompeo said Abe was "relentless in putting them first, the Japanese people first," while also noting that he was "a dear friend of the United States. He knew that a successful United States and a good relationship with us made things better for his own people."

Donald Trump Abe Shinzo

Former U.S. President Trump, left, and Japanese Prime Minister Shinzo Abe pose for a photo prior to their meeting at Akasaka Palace in Tokyo May 27, 2019.  (AP Photo/Eugene Hoshiko, File)

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Former presidents Trump, Obama, and George W. Bush have all spoken highly of their interactions with Abe.

Abe, his country's first prime minister born after World War II, was Japan's longest-serving prime minister. He served from 2006 to 2007 and again in 2012 until he resigned in 2020 after his ulcerative colitis, a chronic condition, resurfaced. He called his decision at the time "gut-wrenching."

 

Fox News' Ben Evansky contributed to this report.