Leaders of some of the world's wealthiest countries have descended on a luxury mountain lodge nestled in Canada's Rockies for this year's G7 summit.

The elite gathering comes as Western allies face numerous crises, from conflicts on three continents to global economic instability.

Canada chairs the G7 this year and will host leaders of Italy, US, France, Germany, UK and Japan in Kananaskis, Alberta. It has promised a set of streamlined priorities focused around the global economy and security.

But Mark Carney's carefully planned agenda has now been upended by the Israel-Iran conflict.

It is his first major international gathering as Canadian prime minister.