Donald Trump and Vladimir Putin shook hands Friday in Da Nang, Vietnam as participants in the Asia-Pacific Economic Cooperation summit met for a group photo, writes dailymail.co.uk.

The two presidents stood next to each other and waved at onlookers as shutters snapped.

Like every other world leader in attendance, Trump and Putin continued one of the annual summit's odder traditions, ditching neckties and dark suits in favor of matching blue silk shirts.

Trump is rarely photographed in anything other than a suit or a golf shirt.

Every president and prime minister at the Da Nang event played along, although Putin upstaged Trump by wearing a dress shirt and tie that was visible underneath his traditional 'ao dai.'

Trump, like everyone else, went open-neck casual.

Vietnam President Trần Đại Quang's team chose the garments, a privilege of host countries that dates back to Bill Clinton at the 1993 APEC summit in Seattle.

That year Clinton gave heads of state matching leather bomber jackets, and some actually wore them.

A year later Indonesia picked up the idea, asking participants to wear traditional patterned batik shirts that some in the U.S. compared to 1960s upholstery.

It could have been worse for Trump: George W. Bush chuckled along with the crowd as he posed in a red woven Chilean poncho in 2008 at the APEC arrival ceremony.

And in Australia the year before, outback raincoats were the order of the day.

Putin and Barack Obama were the only leaders since Clinton's launch to take a break from the tradition.

Obama told world leaders in Hawaii six years ago that they didn't have to play along.

Days after joking that he might pass out 'flowered shirts and grass skirts,' Obama explained that he 'I got rid of the Hawaiian shirts because I looked at pictures of some of the previous APEC meetings and some of the garb that had appeared previously, and I thought this may be a tradition that we might want to break,'

'I suggested to leaders – we gave them a shirt, and if they wanted to wear the shirt, I promise you it would have been fine. But I didn't hear a lot of complaints about us breaking precedent on that one.'

In 2014 he endured a wine-colored jacket in China that drew comparisons to Captain Jean-Luc Picard's uniform in 'Star Trek: The New Generation.'

The White House said as President Trump arrived in Vietnam on Friday that a highly anticipated formal meeting between him and his Russian  counterpart would not be on either leader's schedule.

'Regarding a Putin meeting, there was never a meeting confirmed, and there will not be one that takes place due to scheduling conflicts on both sides,' Trump's press secretary Sarah Sanders told reporters aboard Air Force One. 

'There is no formal meeting or anything scheduled for them.'

'Now, they’re going to be in the same place,' she allowed. 'Are they going to bump into each other and say hello? Certainly possible and likely.'

'But in terms of a scheduled, formal meeting, there’s not one on the calendar and we don’t anticipate that there will be one,' Sanders said.