(Reuters) - 3M Co MMM.N said on Friday it would make more face masks for the United States to fight the coronavirus pandemic, but warned of the "humanitarian implications" of limiting supply to other countries as President Donald Trump directed.

Trump has asked 3M to ramp up imports of the masks to the U.S. from its other global manufacturing facilities, while demanding a pause in the exports of domestically-produced respirators to Canada and some Latin American countries. (bit.ly/3dLDUfT)

“There are, however, significant humanitarian implications of ceasing respirator supplies to healthcare workers in Canada and Latin America, where we are a critical supplier of respirators,” the company said in a statement.

3M said such a move was likely to cause other countries to retaliate as the N-95 face masks made by 3M and other companies are in short supply among healthcare workers treating coronavirus patients.

“If that were to occur, the net number of respirators being made available to the United States would actually decrease.”

Canadian Prime Minister Justin Trudeau said blocking 3M’s export of respirators could backfire, adding that thousands of nurses cross the border to work in Detroit every day.

3M’s response comes a day after Trump slammed the 117-year-old industrial giant in a tweet regarding their mask supply and invoked the Defense Production Act to get the company to produce more respirators. 3M “will have a big price to pay,” he had said, without elaborating. [nL1N2BR01X]

The Defense Production Act, which was passed in 1950, grants the president the power to expand industrial production of key materials or products for national security and other reasons.

U.S. trade adviser Peter Navarro said that the government had some issues making sure that enough of the masks produced by 3M around the world were coming back to the United States.

“The narrative that we aren’t doing everything we can as a company is just not true,” 3M Chief Executive Officer Mike Roman told CNBC television in an interview on Friday.

3M said it will work closely with the Federal Emergency Management Agency to prioritize orders for the masks after saying earlier this week that it expects to ramp up U.S. monthly production of N-95 masks to 50 million in June.

The company said on Friday it has secured China’s approval to export to the U.S. 10 million N-95 respirators manufactured by the company in China.

The Post-it note maker's shares declined as much as 3.6% to $133, compared with a 2.2% fall in the broader S&P 500 index .SPX.