By Vivian Salama, Kim Mackrael and Paul Vieira 

President Donald Trump said Saturday the U.S. wouldn't endorse the final communiqué of the Group of Seven industrial nations summit and threatened to impose auto tariffs in a statement on Twitter that included insults hurled at the Canadian prime minister.

Mr. Trump's unprecedented refusal threw the final hours of the summit, which had ended on a positive note with the joint communiqué, into disarray, raising the specter of an escalating trade battle between allies after what appeared to be a cooling of tensions.

Hours after leaving the G-7 conference in Quebec to fly to Singapore for a meeting with North Korean leader Kim Jong Un, Mr. Trump tweeted that Canadian leader Justin Trudeau had acted "meek" in meetings, then talked tough in a news conference later in the day. His declaration the U.S. wouldn't endorse the communiqué came just hours after the White House told reporters aboard Air Force One that Mr. Trump had joined it.

"Based on Justin's false statements at his news conference, and the fact that Canada is charging massive Tariffs to our U.S. farmers, workers and companies, I have instructed our U.S. Reps not to endorse the Communique as we look at Tariffs on automobiles flooding the U.S. Market," Mr. Trump wrote.

"PM Justin Trudeau of Canada acted so meek and mild during our G-7 meetings only to give a news conference after I left," he wrote. "Very dishonest and weak."

A spokeswoman for Mr. Trudeau said Saturday night that Canada is focused on what was accomplished at the summit. She said Mr. Trudeau's comments represented "nothing he hasn't said before -- both in public and in private conversations with the President."

People from the European delegation, which had pressed the U.S. to agree to language on rules-based trade, reacted with disbelief to Mr. Trump's tweets, one official said.

"We stick to the communiqué as agreed by all participants," an EU official said after the news of Mr. Trump's tweet.

John Kirton, the head of G-7 research group at the University of Toronto, said this marks the first time in G-7 history that there was no unanimity on a communiqué.

Mr. Trump didn't specify any elements of the communiqué he objected to, but his Twitter remarks were a striking turnaround and an example of his penchant for lobbing attacks from afar after amicable interactions in person.

Hours earlier, while Air Force One was in the air to Singapore, an administration official sent a statement to reporters aboard the plane saying that "President Trump has joined the Charlevoix G7 Summit Communique."

At a news conference prior to departing, Mr. Trump said his relationship with French President Emmanuel Macron, German Chancellor Angela Merkel and Mr. Trudeau is "a 10" and that he blames previous U.S. administrations -- not America's allies -- for "bad" trade deals. The president also called for the establishment of a free-trade bloc among the G-7 nations.

Soon after Mr. Trump left Canada, Mr. Trudeau announced that all seven countries had endorsed the communiqué, which states that leaders share a commitment to promoting a "rules-based international order." Under a section entitled "Investing in Growth that Works for Everyone," the statement underlines "the crucial role of a rules-based international trading system and continue to fight protectionism." The communiqué said the nations would "strive to reduce tariff barriers, nontariff barriers and subsidies."

And Mr. Trump's U-turn came moments after Japanese Prime Minister Shinzo Abe praised the G-7 countries for overcoming disagreements on trade to sign the final, joint, statement.

"We know that we need to lead the global economy, that is the sense of responsibility we share," Mr. Abe told reporters after the summit.

However, the apparent consensus on a summit-ending statement didn't stop Mr. Trudeau from issuing sharp words to the U.S. president at a press conference in La Malbaie, Quebec, the site of the G-7 summit, after Mr. Trump had left. His remarks seemed to rankle the U.S. president.

Mr. Trudeau, the summit's host, said member countries had "some strong, firm conversations on trade, specifically American tariffs." In his encounter with Mr. Trump, Mr. Trudeau said he warned the U.S. president that Canada "will not be pushed around" and added it would move forward with retaliatory tariffs against U.S. products in response to levies on Canadian metals.

"We do not want to harm American workers, or harm trade between Canada and the U.S.," Mr. Trudeau said. "But the administration's choice to impose illegitimate and unacceptable tariffs...must be met with clear and firm response. I will do that without flinching."

Mr. Trump said Saturday night that U.S. tariffs on imported steel and aluminum, including from Canada, were a response to Canada's tariffs on dairy. The Trump administration had previously cited national security concerns to justify the tariffs, saying America's allies and rivals are employing unfair trade policies to undermine the viability of critical U.S. industries, starting with steel and aluminum. The administration said the national-security justification comports with U.S. law and a special security exception at the World Trade Organization.

On the same grounds, the Trump administration last month began considering tariffs on imported vehicles and auto parts. Asked at his news conference earlier Saturday how he could justify auto tariffs based on national-security concerns, Mr. Trump responded, "It's very easy. It's economic. It's the balance sheet. To have a great military, you need a great balance sheet."

G-7 member states did have some differences even before Mr. Trump declared the U.S. wouldn't endorse the communiqué. All G-7 members except for the U.S. said they would promote the fight against climate change, while a separate paragraph indicated the U.S. "believes sustainable economic growth and development depends on universal access to affordable and reliable energy resources."

In addition, the U.S. and Japan didn't agree to a statement endorsed by other G-7 members on the threat posed by plastic waste in oceans.

As he was leaving the summit earlier in the day, Mr. Trump said the G-7 should become a "tariff-free" zone but warned that other countries must first change their own trade polices and stop using the U.S. as "a piggy bank everyone is robbing."

"I congratulate the leaders of other countries for so crazily being able to make these trade deals that were so good for their countries and so bad for the U.S.," Mr. Trump said. "But those days are over."

He also indicated his administration would continue to take a tough stance on trade policy as he called for "no tariffs, no barriers...and no subsidies."

The G-7 has never been a tariff-free bloc, with member countries trading among one another under various agreements. The Trump administration recently imposed tariffs on steel and aluminum from the European Union, Canada and Mexico, a move followed last week by reciprocal tariff announcements on a range of U.S. products.

On Saturday, the U.S. president also reiterated his belief that Russia should be allowed back into the group of industrial nations for the sake of world peace, a position that had received lukewarm reception from some other members.

Mr. Trudeau said bringing back Russia was "not something we are even remotely interested in looking at this time." Other countries were also in opposition, according to an official familiar with the deliberations.

Write to Kim Mackrael at kim.mackrael@wsj.com and Paul Vieira at paul.vieira@wsj.com

(END) Dow Jones Newswires

June 09, 2018 22:10 ET (02:10 GMT)

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