WASHINGTON — The steelworkers union blasted Republican candidate Donald Trump Monday, saying it doubts that the New York mogul can bring back steel jobs as he has promised.  But the union has yet to decide on which candidate it will endorse.

“Trump is a consummate salesman, and he has captured the frustration of the American working party, and he is using it as his campaign,” said United Steelworkers Vice President Tom Conway at the USW 2016 Rapid Response and Legislative Conference in Washington.

Conway said workers want a president who would do something to remedy flaws in international trade deals.

In the last 20 years, U.S. steel and aluminum industries have suffered significant job losses and plant closures. USW International Secretary-Treasurer Stand Johnson said issues such as global overcapacity and unfair trade practices are threatening American manufacturing workers.

At a Pittsburgh rally on April 13, Trump promised the crowd that when he is president, “Steel is coming back to Pittsburgh!”

For months, the GOP frontrunner, who has self-funded much of his campaign, has catered his message to working class voters.

Trump’s approach to getting “tough” on trade with China and renegotiating trade deals, such as the North American Free Trade Agreement, has earned him strong support among some blue collar workers. But Conway said his union does not take Trump seriously because his actions as a businessman do not align with his public statements.

Scott Paul, president of the Alliance for American Manufacturing, said “people who say they are for ‘Made in America,’ but do another thing with their own actions — like Donald Trump” lack credibility.

“The man says he’s a business genius, yet, somehow, he can’t figure out how to make a suit in the United States of America,” said Paul, whose organization was created by domestic steel manufacturers and the union.

It’s been widely reported that many of Trump’s signature shirts and ties are produced in China.

Headquartered in Pittsburgh, the USW is the largest industrial labor union in North America, with 1.2 million working and retired members throughout the United States, Canada, and the Caribbean.

Union leaders, while critical of Trump, say the union is waiting for the end of the primary campaign before endorsing a candidate – likely either former Secretary of State Hillary Clinton or Sen. Bernie Sanders.

Carl Matthews, a steelworker from New Orleans, attends the USW 2016 Rapid Response and Legislative Conference in Washington, April 25, 2016. (Xiumei Dong/MNS)

Carl Matthews, a steelworker from New Orleans, attends the USW 2016 Rapid Response and Legislative Conference in Washington, April 25, 2016. (Xiumei Dong/MNS)

Rich Cucarese, a union member employed by the United States Steel Corp. in Pittsburgh, said he backs Sanders because the senator opposes legislation to ratify the Trans-Pacific Partnership trade deal.

But Trump too, strongly opposes the TPP trade agreement, calling it “horrible” and saying he would not stand by it as president.

Jobs at Cucarese’s plant have declined dramatically over the last 20 years, he said. “Trade has decimated our area,” he added.

Carl Matthews, a steelworker from New Orleans, who has been in the industry for 24 years, said he is leaning towards Hillary Clinton because he believes she will keep her promises and make the manufacturing sector robust again.

“I believe she can connect with the people. I believe she knows what manufacturing means to America,” said Matthews.