The Nippon Steel Corp. president said Tuesday the company's planned $14.1 billion acquisition of United States Steel Corp. is important for Japan's economic security and expressed confidence the deal will contribute to growth.

"The United States has without doubt taken the worldwide lead in securing its economic security," Nippon Steel President Eiji Hashimoto said at an online press conference, adding, "We can expect further growth" in the U.S. market as more manufacturers engage in the reshoring of production.

The blockbuster deal announced Monday is the latest instance of a Japanese company seeking growth overseas through an acquisition, with demand at home decreasing due to Japan's shrinking population.

To compete against major rivals, such as China Baowu Group, Nippon Steel needs to create new networks and tap into demand from one of the biggest developed markets, Hashimoto said.

Asked about the hefty premium it is paying for the acquisition, Hashimoto said, "We judged that the deal is economically justifiable," without elaborating further.

Nippon Steel said Monday it will pay $55 per share to make U.S. Steel a wholly-owned subsidiary, offering a 40 percent premium on the U.S. company's Friday closing price of $39.33.

Their combined crude steel output will make Nippon Steel the world's No. 3 steelmaker after China Baowu Group and ArcelorMittal SA, according to 2022 figures from the World Steel Association.

The deal will strengthen the Japanese company's competitiveness in the global market and "will eventually lead to Japan regaining its potential for growth," he said.

The plan to buy the 122-year-old steelmaker, however, sparked criticism from the United Steelworkers union, with the group saying U.S. Steel "chose to push aside the concerns of its dedicated workforce and sell to a foreign-owned company."

The union will "strongly urge government regulators to carefully scrutinize this acquisition and determine if the proposed transaction serves the national security interests of the United States and benefits workers," it said.

Nippon Steel will hold candid talks with the union to gain its understanding, Hashimoto said.

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