TOKYO (Kyodo) -- Japanese Prime Minister Shigeru Ishiba on Wednesday congratulated Donald Trump after the Republican nominee declared victory in the U.S. presidential election, expressing a desire to establish contact with him soon.

Ishiba told reporters he wants to elevate relations with the United States, Japan's longtime security ally, to "new heights" under the next U.S. president.

"I heard Mr. Trump declare victory. I would like to congratulate him from the bottom of my heart," Ishiba said, adding that he respects the democratic choice made by the people of the United States.

"I wish to coordinate closely with him to bring the Japan-U.S. alliance and relationship to new heights," Ishiba said.

Ishiba made the remarks days before he is also expected to be reelected as prime minister in Japan's parliament, following a general election in late October.

While vote counting was still under way, Trump, who has won some of the battleground states, declared victory.

His return to the White House after his first term between 2017 and 2021 comes as Japan is aiming to boost its defense capabilities and spending to counter security threats from an assertive China as well as nuclear-armed North Korea and Russia.

Japan views a robust U.S. presence in the Indo-Pacific region as essential. However, Trump's protectionist streak, as seen in his preference for higher tariffs and bilateral over multilateral trade arrangements in his first term, rattled Japan and other advocates of free trade.

Earlier Wednesday, Japan's top government spokesman Yoshimasa Hayashi said the bilateral alliance will remain the "linchpin of Japan's foreign and security policies" and serve as the "foundation" of peace and prosperity in the region.

"We will closely communicate with the next U.S. administration to further beef up the alliance's deterrence and response capabilities," Hayashi said.

In recent years, Japan and the United States have been deepening their alliance, extending security partnerships to include like-minded countries such as South Korea and Australia.

Foreign Minister Takeshi Iwaya, who previously served as defense minister, underscored the importance of holding high-level summit talks between Ishiba and the next U.S. president.