Donald Trump ditched his necktie and dark suit for one night to don a blue silk shirt at an event in Vietnam.

Other world leaders, including Russian President Vladimir Putin did the same, as it is tradition for those attending the Asia Pacific Economic Cooperation (APEC) summit each year to wear matching attire for a “family photo” of some of the globe’s most prominent politicians.

Every president and prime minister attending the Da Nang event played along.

And with the exception of Mr Putin, they all decided to go open-neck casual. The Russian leader’s white dress shirt and tie was visible underneath his traditional garment.

Mr Trump is rarely photographed wearing something other than a suit or golf shirt.

As part of the tradition, Vietnam President Trần Đại Quang's team chose the garments.

Former President Bill Clinton started the annual tradition back in 1993, when he hosted the summit in Seattle and gifted world leaders in attendance with matching bomber jackets.

Donald Trump's international Presidential trips Show all 22 1 /22 Donald Trump's international Presidential trips Donald Trump's international Presidential trips French President Emmanuel Macron and US President Donald Trump AFP/Getty Images Donald Trump's international Presidential trips French President Emmanuel Macron and US President Donald Trump talk as they leave the Army Museum at Les Invalides in Paris AFP/Getty Images Donald Trump's international Presidential trips German Chancellor Angela Merkel and US President Donald Trump arrive for the group photo at the G7 Taormina summit on the island of Sicily in May 2017 Getty Images Donald Trump's international Presidential trips Mr Trump was pressed on the subject at the G7 summit in Italy Getty Donald Trump's international Presidential trips US President Donald Trump gives a speeech at the Warsaw Uprising Monument on Krasinski Square Getty Donald Trump's international Presidential trips US President Donald Trump and Britain's Prime Minister Theresa May during a ceremony at the NATO headquarters before the start of a summit in Brussels, Belgium Reuters Donald Trump's international Presidential trips Montenegro's Prime Minister Dusko Markovic is seen to the right of Donald Trump at a Nato summit in Brussels REUTERS Donald Trump's international Presidential trips Pope Francis meeting with US President Donald J. Trump EPA Donald Trump's international Presidential trips Pope Francis poses with US President Donald Trump and First Lady Melania Trump AFP/Getty Images Donald Trump's international Presidential trips US President Donald Trump arrives at Palazzo del Quirinale ahead of the meeting with Italian President Sergio Mattarella Ufficio Stampa Presidenza della via Getty Donald Trump's international Presidential trips US President Donald Trump is seen during a joint press conference with the Palestinian leader at the presidential palace in the West Bank city of Bethlehem AFP/Getty Images Donald Trump's international Presidential trips Palestinian president Mahmoud Abbas meets US President Donald Trump PPO via Getty Donald Trump's international Presidential trips Israeli Prime Minister Benjamin Netanyahu speaks with US President Donald Trump prior to the President's departure GPO via Getty Images Donald Trump's international Presidential trips US President Donald Trump and Israel's Prime Minister Benjamin Netanyahu shake hands after delivering a speech at the Israel Museum AFP/Getty Images Donald Trump's international Presidential trips US President Donald Trump and First Lady Melania Trump lay a wreath in the Hall of Remembrance as White House senior advisor Jared Kushner and Ivanka Trump watch on during a visit to the Yad Vashem Holocaust Memorial museum AFP/Getty Images Donald Trump's international Presidential trips US President Donald Trump visit to Yad Vashem Holocaust museum in Jerusalem accompanied by Prime Minister Benjamin Netanyahu GPO via Getty Images Donald Trump's international Presidential trips US President Donald Trump takes his seat before his speech to the Arab Islamic American Summit in Riyadh in Saudi Arabia Reuters Donald Trump's international Presidential trips Saudi Arabia's King Salman bin Abdulaziz al-Saud, US President Donald Trump and US First Lady Melania Trump look at a display of Saudi modern art at the Saudi Royal Court in Riyadh AFP/Getty Images Donald Trump's international Presidential trips US President Donald Trump and Saudi Arabia's King Salman bin Abdulaziz al-Saud take part in a signing ceremony at the Saudi Royal Court in Riyadh AFP/Getty Images Donald Trump's international Presidential trips King Salman presents Donald Trump with The Collar of Abdulaziz al-Saud Medal at the Royal Court Palace on 20 May AP Donald Trump's international Presidential trips US President Donald Trump is welcomed by Saudi King Salman bin Abdulaziz al-Saud upon arrival at King Khalid International Airport in Riyadh AFP/Getty Images Donald Trump's international Presidential trips U.S. President Donald Trump and first lady Melania Trump walk on the South Lawn prior to their first foreign trip Getty Images

The next year, it was his turn to don attire selected by the leader of the summit’s host country – a traditional patterned batik shirt in Indonesia.

The tradition has remained strong ever since, except when ex-President Barack Obama hosted the summit on his own turf in Hawaii in 2011.

Prior to the event, Mr Obama joked that he would make leaders wear aloha shirts or grass skirts.