The G7 may be a small, elite club, but when its leaders gather in Canada, several other national heads will attend as guests -- highlighting the group's efforts to adapt to a fast-changing world.

The leaders of India, Ukraine, Mexico, South Africa and South Korea are among a carefully selected guest list drawn up at a time of global turmoil and a radical new US approach to world affairs.

Summit invitations have become part of the G7 routine, and the host nation often likes to make a "welcome-to-this-exclusive-club" gesture, Ananya Kumar, of the Atlantic Council's GeoEconomics Center, told AFP.

"The leaders want to meet each other, and you'll see the guests being a part of most of the work that happens."

Some hosts "really want certain guests there to show their significance in the global economy," she added.

This year's summit in the Canadian Rockies comes as the G7's share of world GDP has fallen from 63 percent in 1992 to 44 percent today, and as member nations deliberate on troubled relations with China and Russia.

"It's important to........

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