U.S. President Donald Trump meets with Canadian Prime Minister Justin Trudeau at the G-7 summit, Friday, June 8, 2018, in Charlevoix, Canada. (AP Photo/Evan Vucci)

BERLIN — Leaders of the International Monetary Fund, World Trade Organization and other agencies warned Monday that American protectionism could cause global economic damage, while the European Union backed a Group of Seven declaration that U.S. President Donald Trump abruptly refused to join.

At a meeting in Berlin hosted by Chancellor Angela Merkel, the German leader and top officials from a half-dozen international organizations said in a joint statement that the “increasing protectionist tendencies provide us with a clear incentive and opportunity to express our strong support for the multilateral trading system.”

Merkel, fresh from the G-7 meeting in Canada, said those at the meeting were “firmly convinced that sustainable world economic development can only be achieved in cooperation and through win-win situations.”

She said with the Trump administration’s decision to implement new tariffs on aluminum and steel imports to the United States, “multilateralism right now is in a complicated and difficult phase.”

The meeting included the heads of the International Monetary Fund, the World Trade Organization, the Organization for Economic Cooperation and Development, the African Development Bank, the International Labor Organization, and a top World Bank official.

International Monetary Fund head Christine Lagarde told reporters the global economy was in good shape,…