Sunday's summit was announced earlier in the week to involve European leaders, but it takes on a new focus with Ukrainian President Volodymyr Zelenskyy attending, shortly after an explosive meeting on Friday with U.S. President Donald Trump at the White House.
Canada was not mentioned as one of the countries invited to join the Sunday meeting when British Prime Minister Keir Starmer discussed the event during his trip to Washington to meet with Trump earlier this week.
Steve Hewitt, an intelligence researcher who teaches Canadian studies at the University of Birmingham in England, said the fact that Trudeau is going to the summit sends a message on whom Ottawa sees as its partners.