WASHINGTON – President Donald Trump began Labor Day by criticizing the head of the country's largest federation of labor unions.

Trump tweeted that AFL-CIO President Richard Trumka poorly represented his union in a recent television interview.

"Some of the things he said were so (against) the working men and women of our country, and the success of the U.S. itself, that it is easy to see why unions are doing so poorly. A Dem!" Trump tweeted.

In a Fox News interview Sunday, Trumka said Trump has done more to hurt workers than help them. Trumka said the administration has overturned workplace regulations that protect employees and hasn't come up with an infrastructure program that "could put a lot of us back to work."

Wages are down and gas prices are up, he added. And Trumka criticized the tax cuts Trump signed into law, saying they encourage companies to outsource jobs.

"Unfortunately, right now, the scale is weighted against him," Trumka said.

Trump tweeted Monday morning that the American worker is doing better than ever. Unemployment is "setting record lows," he said. And "the U.S. has tremendous upside potential as we go about fixing some of the worst Trade Deals ever made by any country in the world."

The unemployment rate is 3.9 percent, which is not a record. It hit 3.9 percent near the end of Bill Clinton's presidency and dipped to 2.5 percent in 1953 under President Dwight D. Eisenhower.

Trump is in the middle of renegotiating the North American Free Trade Agreement with Canada and Mexico. He reached a tentative deal with Mexico that would provide for duty-free imports of cars assembled in Mexico – but only if at least 75 percent of the parts originate in the U.S. or Mexico. And many of those parts would have to be made by workers earning at least $16 an hour.

Trump told Congress Friday that he wants to go forward with a U.S.-Mexican trade pact to replace the North American Free Trade Agreement even if he can't reach a separate agreement with Canada.

Trumka said Sunday that it's "pretty hard to see how that would work without having Canada in the deal."

Trumka also said a lot more work is needed before the agreement with Mexico is complete.

"If we can't monitor it and enforce it effectively," he said, "then the agreement will fail for workers, and it will fail for the country."

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