A statement from the G7 finance ministers specifically called out the U.S. for its policies.
Japanese Prime Minister Shinzo Abe will have a two-hour meeting with Trump at the White House on Thursday before coming to Quebec. Canada, Japan, Germany, the United Kingdom, France and Italy (six of the G-7) are in accord in pushing back strongly against Trump's aluminum and steel tariffs, though concerted retaliation if necessary.
A few days ago, Trudeau called the metal tariffs-25 percent on steel and 10 percent on aluminum-"insulting".
That move unleashed fury in the Group of Seven industrialized nations and prompted quick retaliation from Canada and Mexico and a promise from the European Union to do so as well, unnerving investors who fear a trade war that could derail the global economy.
"The six countries of the G-7 without the United States are a bigger market taken together than the American market", Macron said, according to Reuters.
A French presidency official said that while G7 members would raise their unhappiness over the tariffs with Mr Trump, they would not deliver an ultimatum that he drop them because the summit "isn't the place where you negotiate things like that".
Trudeau is seen as the best bet to build a bridge between Trump and the rest of the G7 because his government has been able to forge deep links with the US administration and across the various levels of American politics and business, the official said.More news: Teams begin to arrive for the World Cup
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She wonders whether it's a Trump negotiating tactic linked to NAFTA and the G7.
Japan is also expected to take a less confrontational approach than its G7 peers, while quietly pressing its case on trade. The group of nations has a secondary list of items that will be subjected to a new tariffs in three years or possibly sooner, if the WTO rules in the EU's favor.
"Prime Minister Trudeau is being so indignant, bringing up the relationship that the USA and Canada had over the many years and all sorts of other things...but he doesn't bring up the fact that they charge us up to 300% on dairy - hurting our Farmers, killing our Agriculture!" tweeted the President. Japan has said it can not normalize diplomatic relations without the issue's being resolved.
Trump has also told China, the world's second largest economy, to cut its massive trade surplus with the United States.
Trump is said to bristle at the Prime Minister's phone calls, as May launches into policy detail rather than broader conversation. So now it's moving forward with new tariffs on dozens of USA exports, including clothing, whiskey, cranberries, motorcycles, orange juice, boats, peanut butter and more.
Protesters rally ahead of the G7 leaders' summit.
Fears of a looming trade war were heightened last week after all the G7 nations announced plans to retaliate against Trump's tariffs with tariffs of their own.
"The United States must, at long last, be treated fairly on trade", the President tweeted on Saturday.