The United States, Canada, and Mexico are "within inches, maybe millimeters" of closing in on the "largest trade deal in history," Commerce Secretary Wilbur Ross said Tuesday.

"This is the largest trade deal in the history, not just in the U.S., but as far as I can tell, of the whole world," Ross told Fox Business' Maria Bartiromo about the long-awaited USMCA (United States-Mexico-Canada) trade agreement. "I think the remarkable thing is that it took so long to make such small changes insisted on by the Democrats. In effect, they gave [Richard] Trumka, the leader of the [AFL-CIO] union, veto power over the House of Representatives. That seems weird."

Trade Representative Robert Lightheizer, senior White House adviser Jared Kushner, and Canadian Deputy Prime Minister Chrystia Freeland are in Mexico for a signing ceremony Tuesday afternoon, but the deal still hangs on whether it passes a congressional vote.

Ross said a House vote will need to occur this week or shortly after to ensure the trade agreement is passed and signed by the end of the year.

He also explained that the USMCA is expected to create more than 176,000 new jobs while giving a $34 billion boost to the automobile industry, according to International Trade Commission data. It could also create as many as 589,000 new jobs in five years.

Ross said Tuesday the final document is still being tweaked, mainly in the area of labor enforcement.

"Now, the joke there is that the NAFTA agreement had no enforcement provisions, so anything here would be better than what was in NAFTA," said Ross.

But every day that USMCA is not approved is a "day delayed" in its benefits to the United States, said Ross. 

"The 176,000 new jobs aren't going to get created until the USMCA goes in," he said. "All the other improvements, the $34 billion investment in the auto industry, that won't happen until USMCA goes through."

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