Nearly 100 percent of the United States Steel Corp. shareholders who cast votes on Friday regarding Nippon Steel Corp.'s proposed acquisition of the company approved the plan, despite opposition from unionized workers backed by President Joe Biden.

The U.S. steelmaker said, based on a preliminary count of ballots, that more than 98 percent of the votes at a special meeting of shareholders were in favor of its $14.1 billion merger deal with the major Japanese firm. The votes in favor of the transaction represented 71 percent of its outstanding shares.

"The overwhelming support from our stockholders is a clear endorsement that they recognize the compelling rationale for our transaction with (Nippon Steel)," David Burritt, president and chief executive officer of U.S. Steel, said in a statement. "We are one step closer to bringing together the best of our companies."

The Japanese and U.S. companies believe the merger, creating the world's third-largest steelmaker by volume, would benefit both sides. But since the planned all-cash transaction was announced in December, United Steelworkers International has expressed strong opposition, turning it into a political issue.

U.S. Steel's Edgar Thomson Plant near Pittsburgh, Pennsylvania, is shown on April 12, 2024. (Kyodo)

Nippon Steel said in a separate statement it is "confident that this acquisition will protect and grow U.S. Steel and bring significant benefits to its stakeholders, including customers, employees, union workers, suppliers, communities and stockholders -- as well as to the American steel industry and the United States as a whole."

The endorsement by the shareholders marked "a major step toward achieving this goal," it said.

In mid-March, Biden, who wants to secure support from labor unions for the November presidential election, said the iconic steelmaker should be domestically owned.

"It is important that we maintain strong American steel companies powered by American steel workers. I told our steel workers I have their backs, and I meant it," Biden said in a statement.

Former President Donald Trump, who is running against Biden in a bid to return to the White House, has also said he would "block" Nippon Steel's plan.

U.S. Steel, founded in 1901, is headquartered in Pittsburgh, Pennsylvania, a key battleground state in the presidential election.

The Biden administration has said Nippon Steel's plan should be scrutinized in terms of its potential impact on national security, despite the offer being from a key U.S. ally.

Nippon Steel has said its advanced production technology would improve the operations of the U.S. firm, which was once an industrial leader but has fallen to 27th in global output.

The Tokyo-headquartered company has also promised to leave the name and branding of U.S. Steel unchanged, while vowing no jobs would be lost as a result of the acquisition, under which it offered to pay $55 per share, representing a 40 percent premium over the stock's closing price before the December announcement.

In the days leading up to a formal meeting between Biden and Japanese Prime Minister Fumio Kishida on Wednesday, senior officials of the two countries were repeatedly asked whether Nippon Steel's bid to buy U.S. Steel was on the agenda.

During a press conference after the summit at the White House, the U.S. and Japanese leaders were also asked whether they had discussed the matter, but both of them dodged the question.

"Japan believes that appropriate procedures based on law are being implemented by the U.S. government," Kishida said. "Japan is the largest investor in the United States. Japanese businesses employ about 1 million workers in the United States."

"Investment from Japan is on an ever-increasing trend. We hope to continue to ensure such a win-win situation for both countries," he said.

Biden said, "I stand by my commitment to American workers. I'm a man of my word, I'm going to keep it," adding he also stands by his commitment to maintaining a "strong alliance" with Japan.

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