Maybe the signature handshakes have gotten too old.

US President Donald Trump on Saturday doubled back ? twice! ? to fetch the hat of a Marine who stood guard as the former was about to go aboard his aircraft.

The incident occurred at the Andrews Air Force Base, near Washington, where Trump hopped from the inbound plane from Germany ? after G20 summit ? to his presidential helicopter.

Trump retrieved the white hat from the ground, went to put it back on the Marine's head, and patted him on his arm, when the strong winds blew it off again.

The American president then went back one more time to get the officer's hat but handed it to a fellow officer, allowing to climb the stairs up into his helicopter.

The soldier remained strictly in his position ? showing discipline ? and didn't move once, not even to look where his hat had flown off to.

Trump was attending the G20 summit in Hamburg, Germany, for the past two days. There, he met with global leaders, including German Chancellor Angela Merkel, Russian President Vladimir Putin, French President Emmanuel Macron, and Canadian Prime Minister Justin Trudeau.