Washington (CNN) President Donald Trump and first lady Melania Trump paid their respects to fallen American troops during an unannounced visit to Arlington National Cemetery ahead of Memorial Day.

During their 20-minute visit Thursday afternoon, the first couple laid flags in section 34 of the cemetery, placing flags on the headstones of Frank Buckles, who was the last living World War I veteran, among others, according to the White House press pool.

The visit comes ahead of Memorial Day weekend -- which the President will spend in Japan.

The first couple leave for Japan on Friday, and will not be on US soil Monday for the traditional ceremonies honoring those who served in the armed forces. White House press secretary Sarah Sanders said the President will also hold a Memorial Day event while in Japan, but he wanted to visit Arlington as well.

The cemetery is the final resting place for over 400,000 men and women, and each year for Memorial Day a flag is placed by every tombstone.

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