Japanese Prime Minister Shinzo Abe took U.S. President Donald Trump out to play golf near Tokyo on Sunday, an activity that has become a tradition when the two leaders meet.

After their latest round of golf diplomacy, Abe and Trump, along with their wives, watched sumo at Tokyo's Ryogoku Kokugikan before having an informal dinner at a traditional Japanese charcoal grill restaurant in Tokyo.

(U.S. President Donald Trump (R) prepares to board a helicopter at Akasaka Press Center, a U.S. Army facility in Tokyo.)

The helicopter was bound for the Mobara Country Club in Chiba Prefecture near Tokyo, where they played their fifth round together since the U.S. leader took office in 2017.

[Pool photo/Kyodo]

[Pool photo/Kyodo]

The Japan Sumo Association has scrambled to implement security measures, some of them unprecedented, ahead of Trump's attendance.

In a very unusual step in the long history of sumo in its present form of professional bouts, the association asked spectators coming to the last day of the Summer Grand Sumo Tournament to submit their personal information including name.

(People take photos of U.S. President Donald Trump with their smartphones.)

[Pool photo/Kyodo]

[Pool photo/Kyodo]

(Summer Grand Sumo Tournament winner Asanoyama (R) loses to Mitakeumi on the final day of the tournament at Tokyo's Ryogoku Kokugikan.)

(U.S. President Donald Trump (L) walks onto the raised ring for the award ceremony for Summer Grand Sumo Tournament winner Asanoyama (R) at Ryogoku Kokugikan.)

(Summer Grand Sumo Tournament winner Asanoyama (L) receives a special American-made trophy from U.S. President Donald Trump.)

Before holding an official meeting with Abe on Monday, Trump and first lady Melania will meet with new Emperor Naruhito and Empress Masako.

He will be the first foreign leader to meet with the emperor, who ascended the Chrysanthemum Throne on May 1 after former Emperor Akihito abdicated the previous day, the first Japanese monarch to stand down in about 200 years.

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