President Donald Trump brought his America First message to Boeing's South Carolina plant Friday, touting his goal to boost U.S. manufacturing and threatening companies that consider moving jobs abroad.

Standing in front of a new Boeing 787-10 Dreamliner passenger aircraft made at in North Charleston, Trump repeated his campaign promises to promote American production that partly fueled his dizzying path to the White House. He warned of a "substantial penalty" for companies that move jobs out of the United States.

"We want products made by our workers in our factories stamped with those four magnificent words — made in the USA," Trump said.

Trump's trip comes at a complicated time for his economic agenda of tax cuts and regulatory rollback. Trump has promised a tax reform plan in the coming weeks, but Republican congressional efforts to introduce a health-care bill and disagreements among lawmakers and business stakeholders about tax legislation threaten to hold up tax reform for months or even into next year.

A possible border adjustment provision, part of House Republicans' tax plan, complicates Trump's made in America pledges and could affect numerous companies like Boeing. Boeing gets some of its parts from outside of the U.S.

"Our goal as a nation must be to rely less on imports and more on products made here in the USA," Trump said.

The president repeated his administration's goal to "buy American and hire American," something his family's companies have not consistently done.

Trump's visit to Boeing also came two days after an attempt to unionize the plant fell far short, dealing a blow to organized labor, which largely backed Democrat Hillary Clinton in the election.

Trump has repeatedly used his position to try to extract promises out of American companies. He put Boeing on notice in December before he took office, slamming the company for the cost of its Air Force One program and sending its shares lower.

Boeing has since pledged to cut the program's costs.

Trump said "it looks like we're getting closer and closer" to reaching a deal on Air Force One cost cuts. He added that "we are seriously looking at a big order" of Boeing F-18 Super Hornet fighter jets, which would mark a blow to Lockheed Martin and its F-35 program.

The president has previously appeared to pit the two aircraft makers against one another.

Trump's divisive executive order on immigration, which included countries like Iran and Iraq, also put about $20 billion worth of Boeing commercial aircraft orders at risk.