The director of the U.S. National Economic Council said Thursday the body was ready to look into a planned $14.1 billion acquisition of United States Steel Corp. by Japan's Nippon Steel Corp. amid opposition to the deal from politicians and unions.

President Joe Biden "believes the purchase of this iconic American-owned company by a foreign entity -- even one from a close ally -- appears to deserve serious scrutiny in terms of its potential impact on national security and supply chain reliability," Lael Brainard said in a statement.

"This administration will be ready to look carefully at the findings of any such investigation and act if appropriate," she said, after the top Japanese steelmaker said Monday that it would make the U.S. firm its subsidiary and create the world's third-largest steelmaker by volume.

File photo taken in May 2019 shows a sign of Nippon Steel Corp. at the building housing the company's headquarters in Tokyo. (Kyodo)

Since the announcement of the buyout plan, some members of the U.S. Congress and the United Steelworkers union have expressed opposition to the deal.

The statement by Brainard comes as Biden prepares for the presidential election next year. Pennsylvania, where U.S. Steel is based, is expected be a battleground state.

On Friday, Nippon Steel said in a statement that the company believes the acquisition will benefit all stakeholders, adding it will engage in dialogue with parties concerned to seek their understanding.

Meanwhile, two Democratic senators and one Democratic member of the House of Representatives from Pennsylvania sent a letter dated Tuesday to Janet Yellen, chair of the Committee on Foreign Investment in the United States, asking her to block the deal.

"We urge you to consider the national security implications of selling a company manufacturing some of our most important industries, including defense, power, and infrastructure, to a foreign company," the text of the letter said.


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