TOKYO (Kyodo) -- Nippon Steel Corp. is set to file a lawsuit in response to U.S. President Joe Biden's decision to block its $14.1 billion takeover of United States Steel Corp., sources close to the matter said Saturday.

Biden on Friday said the deal posed a risk to national security while urging the Japanese and U.S. steelmakers to "fully and permanently" abandon their plan, which has been backed by U.S. Steel shareholders. The leadership of the powerful United Steelworkers union strongly objected to the acquisition.

Nippon Steel, the world's fourth-largest steelmaker, and the smaller U.S. Steel immediately released a joint statement saying the U.S. authorities' review of their deal was "manipulated to advance President Biden's political agenda" and that they will "take all appropriate action to protect our legal rights."

Biden's order marked the first time an American president has banned a merger and acquisition deal involving a Japanese firm.

Biden, who leaves office on Jan. 20, and President-elect Donald Trump have both publicly opposed the deal, which was initially announced in 2023 and became highly politicized ahead of the November U.S. presidential election.

The two firms are expected to claim in court that Biden did not present sufficient evidence to prove the acquisition poses a threat to U.S. national security, and that his decision violates due process under the U.S. Constitution and the law governing the Committee on Foreign Investment in the United States.

The committee reviewed the deal but said last week it could not reach a consensus, leaving the decision to Biden, according to the companies.