Leaders of some of the world’s biggest economic powers arrive in the Canadian Rockies on Sunday (June 15, 2025) for a Group of Seven summit, overshadowed by an escalating conflict between Israel and Iran and U.S. President Donald Trump’s unresolved trade war with allies and rivals alike.

Israel’s strikes on Iran and Tehran’s retaliation, which appeared to catch many world leaders unawares, are the latest sign of a more volatile world as Mr. Trump seeks to withdraw the U.S. from its role as world policeman.

Speaking on a flight to Canada to attend the summit, British Prime Minister Keir Starmer said he had discussed efforts to de-escalate the crisis with Mr. Trump and Israeli Prime Minister Benjamin Netanyahu, as well as other world leaders.

Britain is sending fighter jets and other military reinforcements to the Middle East.

“We do have longstanding concerns about the nuclear programme Iran has. We do recognise Israel’s right to self-defence, but I’m absolutely clear that this needs to de-escalate. There is a huge risk of escalation for the region and more widely,” Mr. Starmer said, adding he expected “intense discussions” would continue at the summit.