President Donald Trump signed a memorandum Monday morning to leave the proposed Pacific Rim trade pact known as the Trans-Pacific Partnership.

The move is basically a formality, since the agreement had yet to receive required Senate ratification. Trade experts say that approval was unlikely to happen given voters' anxiety about trade deals and the potential for job losses.

Trump called the move "a great thing for the American workers"

It remains unclear if Trump would seek individual deals with the 11 other nations in TPP— a group that represents roughly 13.5 percent of the global economy, according to World Bank figures.

Trump has blamed past trade deals such as the North American Free Trade Agreement and China's entrance into the World Trade Organization for a decline in U.S. factory jobs.

Trump also is expected to sign an executive order as early as Monday intended to renegotiate the NAFTA free trade agreement between the United States, Canada and Mexico, NBC News reported, citing an unidentified White House official.

The TPP, a 12-country deal that sought to liberalize trade between the U.S. and Pacific Rim nations including Japan, Mexico and Singapore, was a signature piece of former President Barack Obama's "pivot" to Asia. Trump campaigned against the pact and other trade deals, such as the North American Free Trade Agreement, during his campaign for the White House.

The president said on Sunday he planned talks soon with the leaders of Canada and Mexico to begin renegotiating NAFTA.

"We will be starting negotiations having to do with NAFTA," Trump said at a swearing-in ceremony for his top White House advisers. "We are going to start renegotiating on NAFTA, on immigration and on security at the border."

Trump said during the campaign he wanted to secure more favorable terms for the United States in the NAFTA pact.

NAFTA, which took effect in 1994, and other trade deals became lightning rods for voter anger in the U.S. industrial heartland states that swept Trump to victory.

In a video in November, Trump said he would withdraw from the TPP pact, which hasn’t been ratified, on "Day One." He called the trade deal "a potential disaster for our country."

Trump's press secretary, Sean Spicer, promised Thursday that Trump would act "very shortly" to fulfill his campaign promise to do so.

The Associated Press, Reuters, and Bloomberg News contributed to this report.