Leaders and governments around the world expressed concern over Japanese Prime Minister Shinzo Abe's health on Friday after the 65-year-old announced his impending resignation for health reasons, while some also praised his leadership during nearly eight years in office.

Together with U.S. President Donald Trump, Abe has "made the U.S.-Japan alliance, and our overall relationship, the strongest it has ever been," a senior Trump administration official said in a statement.

Japanese Prime Minister Shinzo Abe (C) leaves his office after announcing his decision to resign due to health issues at a press conference in Tokyo on Aug. 28, 2020. (Kyodo)

"We look forward to working with Prime Minister Abe's successor in further strengthening our nations' ties and advancing our shared goals," the official said.

After news reports of Abe intention to resign, Chinese Foreign Ministry spokesman Zhao Lijian declined to comment, saying it was a matter of Japan's internal affairs. But he told reporters that China "wants to continue to promote improvement and development of ties" with Japan.

South Korean President Moon Jae In's office said Abe's announcement was "regrettable" as the prime minister "played multiple roles in improving relations between South Korea and Japan."

"Our government will continue to work together with a new prime minister and Cabinet to improve South Korea-Japan ties," presidential spokesman Kang Min Seok said. "We hope he gets well as soon as possible."

There was no immediate reaction from the North Korean government via the country's state media.

Taiwan's President Tsai Ing-wen thanked Abe for his strong support for Taiwan over the years in the face of China's efforts to isolate the self-ruled island diplomatically, and his efforts to promote Taiwan-Japan relations.

Tsai was quoted by Presidential Office spokesman Xavier Chang as also saying that she "sincerely hopes that Abe will recover his health at an early date."

Indian Prime Minister Narendra Modi, addressing Abe directly in a tweet, said he was "pained to hear about your ill health, my dear friend."

"In recent years, with your wise leadership and personal commitment, the India-Japan partnership has become deeper and stronger than ever before. I wish and pray for your speedy recovery."

In Singapore, Prime Minister Lee Hsien Loong issued a statement on Facebook saying he is "sorry" to learn Abe is resigning for health reasons. Saying he had worked well with the Japanese leader over the years, Lee said, "Under his leadership, our bilateral relations have deepened."

Lee also credited Abe with playing a "critical role" in concluding an 11-member Trans-Pacific Partnership free trade pact, after the United States withdrew from its original framework in 2017 under President Trump.

Thai Foreign Minister Don Pramudwinai told reporters that Prime Minister Prayut Chan-o-cha expressed concern about Abe's health and wished him a quick recovery.

The foreign minister said the coming leadership change in Tokyo would not shake Thailand's confidence in Japan as it has a stable political system.

Philippine Foreign Secretary Teddy Locsin said on Twitter that Abe is a "very good friend of the Philippines" and a "close personal friend" of President Rodrigo Duterte.

He called him "an imposing political presence in person."

Pakistani Prime Minister Imran Khan tweeted, "Great progress has been made in Pakistan-Japan ties under PM @AbeShinzo with relations being further strengthened under his leadership, leading to enhanced cooperation in all areas."

"We send our best wishes for his good health and future endeavors," Khan added.

Japanese Prime Minister Shinzo Abe bows after announcing his intention to resign at a news conference in Tokyo on Aug. 28, 2020, citing a flare-up of his long-running intestinal disease. (Kyodo)

One of the most personal and sympathetic reactions came from Australia.

"On behalf of the people of Australia, I would like to thank" Abe "for his enduring commitment to Australia-Japan relations over his long and successful career," Prime Minister Scott Morrison said in a statement.

"Shinzo Abe is a true friend. He is Australia's true friend. Japan is one of Australia's closest partners, propelled by Prime Minister Abe's personal leadership and vision, including elevating the relationship to new heights under our Special Strategic Partnership."

In Europe, British Prime Minister Boris Johnson wished Abe "good health."

"Shinzo Abe has achieved great things" for both Japan and the world, Johnson said on Twitter. "Under his stewardship the UK-Japan relationship has gone from strength to strength in trade, defense and our cultural links."

Abe announced he would be stepping down because he needs to be treated for a flare-up of the intestinal disease that led to his previous resignation as premier in 2007.

Following that first one-year stint, Abe returned as prime minister in December 2012. Earlier this week, he became Japan's longest-serving prime minister in terms of consecutive days in office.

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