US President Joe Biden was inadvertently a missing man in the traditional photo of world leaders at the final Group of 20 summit of his presidency – a photo-shoot fail that US officials attributed to timing.

Instead, Biden and Canadian Prime Minister Justin Trudeau strolled up after photographers had already taken the official picture, as other world leaders milled about chatting after having smiled and raised linked hands for the photo. Italian Prime Minister Giorgia Meloni also missed the group photo, a set piece of such summits.

South Africa's Cyril Ramaphosa, China's Xi Jinping and Australia's Anthony Albanese. – AP

Biden and Trudeau arrived together at the designated spot for the photo, standing and looking about for a time. 

The timing left Chinese President Xi Jinping front and centre among the rows of leaders posed against blue skies and blue water in Rio de Janeiro.

Russian Foreign Minister Sergey Lavrov stood, less visible, in a back row.

A senior Biden administration official, who was not authorised to comment publicly, said Biden and other leaders missed the photo because of “logistical issues”. Biden had intended to be part of the photo, but it occurred earlier than scheduled.

G20 leaders, guests pose for group photo in Rio. – AP