President Trump appears to be caught off guard by ASEAN summit's group handshake

— -- President Donald Trump, who is known for his trademark, prolonged and at times aggressive, handshakes with world leaders, was momentarily caught off guard executing a different kind of handshake, at an international summit in the Philippines on Monday.

Trump was in Manila attending the Association of Southeast Asian Nations summit, which began with an opening ceremony and photo op of attending world leaders. The heads of state were invited on stage to participate in the conference's traditional ASEAN group handshake, in which each leader crosses their arms and joins opposite hands with the leaders next to them.

Photographs captured Trump as he seemed momentarily confused by the handshake.

President Trump appeared to be awkwardly hugging himself once he got into the cross-armed, handshake position.

After some effort and grimacing, Trump smiled as he successfully executed this traditional handshake.

ABC News’ Jordan Phelps contributed to this report.