TOKYO — Japan’s largest steelmaker defended its proposed acquisition of U.S. Steel on Friday as a way to strengthen “American supply chains and economic defenses against China,” a day after President Joe Biden came out against the deal.

Nippon Steel said it was determined to complete the $14 billion takeover agreed to in December, which has raised concerns about the implications for union workers, supply chains and U.S. national security.

“Through increased financial investment and the contribution of our advanced technologies to U.S. Steel, Nippon Steel will advance American priorities by driving greater quality and competitiveness for customers in the critical industries that rely on American steel while strengthening American supply chains and economic defenses against China,” the Tokyo-based company said in a statement.

“No other U.S. steel company on its own can meet this challenge while also meeting antitrust requirements,” it added.

The company said that under its proposal, there would be no layoffs or plant closures as a result of the transaction.

On Thursday, Biden said Pittsburgh-based U.S. Steel should remain American-owned.

“It is important that we maintain strong American steel companies powered by American steel workers,” he said in a statement released by the White House. “I told our steel workers I have their backs, and I meant it.”

“U.S. Steel has been an iconic American steel company for more than a century, and it is vital for it to remain an American steel company that is domestically owned and operated,” he added.

The United Steelworkers union welcomed Biden’s remarks.

“Allowing one of our nation’s largest steel manufacturers to be purchased by a foreign-owned corporation leaves us vulnerable when it comes to meeting both our defense and critical infrastructure needs,” David McCall, the president of United Steelworkers International, said in a statement.

Asked about Biden’s remarks on Friday, Japanese Chief Cabinet Secretary Yoshimasa Hayashi declined to comment on matters concerning the management of individual companies.

He added that the U.S.-Japan alliance “has never been stronger” and that the two countries will continue to work closely together “to achieve sustainable and inclusive economic growth in the Indo-Pacific region and to maintain and strengthen a free and open economic order.”

Arata Yamamoto reported from Tokyo, and Jennifer Jett reported from Hong Kong.