American President Donald Trump criticized the United States’ trade partners, including those in Europe and Canada, on Monday.

Trump wrote on Twitter that the U.S. will no longer accept what he called unfair trade, even from friendly countries.

“We must put the American worker first,” he tweeted.

On Saturday, he called the situation “Trade Abuse.”

Trump tweeted Monday from Singapore. He traveled there following the meeting in Canada of leaders of the Group of Seven major industrial nations.

The G7 is Britain, Canada, France, Germany, Italy, Japan and the U.S.

The leaders met in the area of Charlevoix, Quebec on June 8 and 9. The discussions were marked by disputes with the United States over trade and Russia. The United States did not agree to the G7 meeting final statement.

After it ended, U.S. President Donald Trump published a tweet that said he had told his trade representatives “not to endorse the Communique.”

Canadian Prime Minister Justin Trudeau spoke to reporters at the close of the meeting on Saturday. He said that Canada would order “retaliatory” measures against U.S. products as soon as July 1.

The Trump administration ordered taxes on steel and aluminum imports from Canada and other allies earlier this year.

Trudeau said that Canada would “not be pushed around.”

Several leaders said they did not support the idea of Russia rejoining the group of economic powers. Russia was expelled after it took over Crimea in 2014. Members also say Russia continues to support separatists in eastern Ukraine.

Trudeau said he was not “remotely interested” in having Russia rejoin the group.

British Prime Minister Theresa May agreed. She said Russia had failed to meet the terms of the Minsk agreements meant to end the conflict in Ukraine.

Before the meeting, Trump had voiced support for Russia taking part.