Nippon Steel released a statement Tuesday arguing that the Japanese firm's planned acquisition of U.S. Steel would benefit the United States, after U.S. Vice President Kamala Harris expressed her opposition to the buyout plan the previous day.

"We're confident that Nippon Steel's acquisition of U.S. Steel will revitalize the American steel rust belt, benefit American workers, local communities, and national security in a way no other alternative can," Nippon Steel said. "We believe that a fair and objective regulatory review process will support this outcome, and we look forward to closing the transaction as soon as possible."

Nippon Steel said last month that it would make an additional investment of about $1.3 billion in U.S. Steel following the takeover. The Japanese firm stressed that only it was able to carry out such a large investment, and that "U.S. Steel and the entire American steel industry will be on much stronger footing."