U.S. President-elect Donald Trump extended further the list of business-related pledges following elections as he announced he would “block” a planned takeover of U.S. Steel by Japanese company Nippon Steel, a deal worth $14.9 billion, including debts.

“I am totally against the once great and powerful U.S. Steel being bought by a foreign company, in this case Nippon Steel of Japan,” Trump wrote on his Truth Social platform.

“Through a series of Tax Incentives and Tariffs, we will make U.S. Steel Strong and Great Again, and it will happen FAST! As President, I will block this deal from happening.”

Embattled U.S. Steel has argued that it needs the Nippon deal to ensure sufficient investment in its Mon Valley plants in Pennsylvania, which it says it may have to shutter if the sale is blocked.

Nippon Steel said after Trump’s comments that it was “determined to protect and grow U.S. Steel in a manner that reinforces American industry, domestic supply chain resiliency, and U.S. national security.”

“We will invest no less than $2.7 billion into its unionized facilities, introduce our world-class technological innovation, and secure union jobs so that American steelworkers at U.S. Steel can manufacture the most advanced steel products for American customers,” the Japanese firm said in a statement.

Days after the U.S. election last month, Nippon Steel said it expected to close its takeover of the company before the end of the year while U.S. President Joe Biden was still in office.

Biden, too, has opposed the deal, saying it was “vital” for U.S. Steel “to remain an American steel company that is domestically owned and operated.”

The deal is being reviewed by a body helmed by Treasury Secretary Janet Yellen that audits foreign takeovers of U.S. firms, called the Committee on Foreign Investment in the United States (CFIUS).

In September, Biden’s administration extended their review, pushing a conclusion on the politically sensitive deal until after the Nov. 5 presidential election.

A Nippon Steel earnings presentation on Nov. 7 maintained that “the transaction is expected to close in … calendar year 2024,” pending a U.S. national security review.

“Unless the situation changes dramatically, I believe the conclusion will come by the end of the year,” during Biden’s time in office, vice chairperson Takahiro Mori told reporters.

Trump will be inaugurated on Jan. 20.

Protectionist policies

On the campaign trail, he vowed to install protectionist economic policies to help support U.S. businesses, including threats to restart a trade war with the world’s second-largest economy, China.

While running for the White House, he specifically promised to block Nippon’s takeover of U.S. Steel, which is based in the key political battleground state of Pennsylvania.

Trump’s vice presidential pick, J.D. Vance, also led congressional opposition to the takeover in the U.S. Senate, where the deal has been criticized by both Republicans and Democrats.

Analysts had suggested that Trump’s position could soften after the election was over, but Monday’s statement indicated that was not the case.

Major Japanese and American business groups have urged Yellen not to succumb to political pressure when reviewing the proposed acquisition.

The steelworkers’ union fought the deal and criticized a September arbitrators’ ruling that Nippon had proven it could assume U.S. Steel’s labor contract obligations.

In September, however, some U.S. Steel workers rallied to support the deal, arguing it would help keep plants open.