Prime Minister Yoshihide Suga plans to speak with U.S. President Donald Trump by phone on Sunday night, Japanese government sources said Friday, in what will be their first conversation since Suga took office.

Suga, leader of the Liberal Democratic Party, was elected Japan's first new prime minister in nearly eight years by parliament on Wednesday to succeed his predecessor Shinzo Abe, who had built one of the closest relationships with Trump among world leaders.

Suga has vowed to continue on the path set out by Abe, who resigned for health reasons, by keeping the security alliance with the United States as the cornerstone of Japan's foreign policy.

"Congratulations Prime Minister Yoshihide Suga. You have a great life story! I know you will do a tremendous job for Japan and for the world. Look forward to talking soon!" Trump tweeted on Thursday.

Japan's top government spokesman, Chief Cabinet Secretary Katsunobu Kato, on Friday expressed thanks for Trump's "heartwarming message" and stressed the importance of Japan-U.S. relations.

Speaking at a press conference, Kato said arrangements were being made for the leaders to speak by phone "at an early time."

Meanwhile, the prime minister's office said that Suga's national security adviser, Shigeru Kitamura, will travel to Washington next week to meet with his counterpart Robert O'Brien.

The two are slated to discuss the situation in the Indo-Pacific region and ways to further strengthen the long-standing alliance, it said.

Suga, who was Abe's right-hand man as chief Cabinet secretary during his predecessor's tenure since late 2012, is seen as a politically-savvy operator on the domestic front but is known to have little experience in foreign diplomacy.

It remains to be seen whether the 71-year-old will be able to form the kinds of personal relationships with world leaders that his predecessor did during a record-long tenure.

Abe and Trump played golf together on multiple occasions, and the U.S. president invited the then-prime minister to his Mar-a-Lago estate in Florida twice, in 2017 and 2018.

In a statement following Suga's inauguration, the White House said Trump is "ready to continue pursuing the vision of a free and open Indo-Pacific that he and former Prime Minister Shinzo Abe forged."

"The relationship between the United States and Japan has never been stronger, and President Trump looks forward to working with Prime Minister Suga to make it even stronger," it said.

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