Leaders of some of the world’s biggest economic powers arrived in the Canadian Rockies on Sunday 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, Associated Press reported.

Israel’s strikes on Iran and Tehran’s retaliation, which appeared to catch many world leaders unawares, is the latest sign of a more volatile world. 

Trump in recent days vetoed an Israeli plan to kill Iran’s Supreme Leader Ayatollah Ali Khamenei, a U.S. official told The Associated Press, in an indication of how far Israel was prepared to go.

British Prime Minister Keir Starmer said he had discussed efforts to de-escalate the crisis with Trump and Israeli Prime Minister Benjamin Netanyahu, as well as other world leaders and said he expected “intense discussions” would continue at the summit, according to Associated Press.