Japan's Minister of Economy, Trade and Industry: "It is difficult to understand. We have no choice but to take it seriously."

Following US President Joe Biden's formal ban of Japanese steelmaker Nippon Steel Corp.'s planned \$25billion acquisition of American competitor US Steel, Japanese Minister for Economy and Industry Yasutoshi Nishimura called the decision by Biden's administration "very difficult to understand" on Tuesday.

"It is extremely difficult and regrettable for the Biden administration to explain (the decision), in light of national security concerns," Nishimura said in a statement to news agency AFP. "Japan's government has no choice but to take this business seriously and act properly based on objective viewpoints of facts and reasons presented."

According to Japan'sKyodo Newsagency, late on Monday, Nishimura said that, "The Japanese government believes that the proposed acquisition will be beneficial to the United States and Japan. Japan's direct investment into the country has been on a long-term growth trend in recent years."

Japan, said Nishimura, "strongly wishes to continue to further enhance (its) US investment and strengthen alliance through cooperation" with the US. "It is necessary for (the) (US) government to appropriately respond to Japan's concerns, based on its commitment to rules of procedure for fair decision-making," he added. "I would like them to explain (the reasons) for this (merger approval) decision in accordance with the process of the Committee on Foreign Investments in the United States (CFIUS), for example."

On Jan. 3, the White House announced that Biden has formally barred Nippon Steel's proposed purchase of US Steel. "A strong domestic steel industry that is owned and operated by US nationals is an important national security priority," read a statement from the White House citing Biden's determination. Among other things, it said, "Nippon Steel's acquisition of US Steel would place one of the largest steel producers in the United States under the control of a foreign entity, jeopardizing national security and critical supply chains," according to the statement.

The ultimate determination against the acquisition drew criticism from Japanese and US steel industry officials alike. "The companies jointly regret the determination by the Committee on Foreign Investment in the United States (CFIUS)," Nippon Steel and US Steel said in a statement posted to the Japanese firm's website late on Tuesday.

"Nippon Steel and US Steel have always understood the determination process is confidential and based on an objective review of facts. Unfortunately, this decision is clear evidence this merger was decided based on a political consideration," the two companies were quoted as saying by AFP, adding that they "reserve the rights and options available to them, up to and including litigation." Meanwhile, according to the Japanese newspaperNikkei early Wednesday morning local time, following Biden's decision Nippon Steel Corp. decided to take legal action against the Biden administration's decision.