U.S. President Donald Trump threw his support "100 percent" behind Prime Minister Shinzo Abe over a one-year postponement of the Tokyo Olympics this summer, calling it a "wise and great" decision during their phone talks on Wednesday, the Japanese government said.

A day after the International Olympic Committee board endorsed the delay due to the coronavirus pandemic, Abe briefed Trump on the schedule change and the two leaders agreed to work closely to realize the games in a "complete" way as proof that humankind has beaten the virus, it said.

"President Trump repeatedly said the postponement was a very wise and great decision and he expressed support for the prime minister's stance," Chief Cabinet Secretary Yoshihide Suga said at a press conference.

Trump was the first foreign leader Abe held phone talks with after the prime minister and IOC President Thomas Bach agreed Tuesday night to postpone the games, initially set to begin on July 24. The major sporting event will be held no later than the summer of 2021.

Despite insisting that the Tokyo Games would go ahead as planned, both host Japan and the IOC had faced mounting pressure from athletes and sports officials to rethink the timing. Earlier in the month, Trump suggested that the games may have to be postponed for a year.

In the phone conversation that lasted about 40 minutes, Abe explained to Trump that the delay is to make sure athletes from around the world can compete at their best and the games are safe and secure for spectators.

The coronavirus outbreak, which began in China's Wuhan late last year, has become a global pandemic with over 400,000 infections worldwide. The epicenter has shifted to Europe and the United States.

Abe and Trump agreed to cooperate over their response to the coronavirus, including the development of drugs to treat COVID-19, the respiratory illness caused by the virus, according to Suga, the top Japanese government spokesman.

To contain the spread of the virus, Japan is set to start asking all travelers from the United States to self-quarantine for 14 days, in a new measure from Thursday to the end of April. The U.S. State Department has already advised Americans to avoid all international travel.

Trump said on Twitter after the phone talks that he believes the postponed games will turn out to be "a great success," adding, "I look forward to being there!"

Abe previously spoke with Trump by phone on March 13 after the U.S. president referred to a one-year postponement. At the time, Abe told Trump that Japan was making preparations to hold the games.

But the IOC said Sunday that various options, including postponement, would be weighed over the next four weeks. Abe has said in a parliamentary session that a delay would be an option if the games could not be held in a "complete way," meaning that there should be spectators and no downsizing.

Abe also spoke with Australian Prime Minister Scott Morrison on Wednesday and agreed that Japan and Australia will coordinate closely to achieve a complete games, according to the Japanese Foreign Ministry.

Morrison respected Abe's decision to push back the games until the summer of 2021 at the latest, the ministry said.

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