Multiple US media outlets say President Joe Biden has decided to officially block Japan's Nippon Steel from purchasing US Steel.

The Washington Post and others reported on Thursday that a White House announcement is planned as early as Friday.

Nippon Steel has declined to comment on the reports.

The two steelmakers inked the acquisition deal in December 2023.

The Committee on Foreign Investment in the United States later began reviewing the plan over national security risks, but was unable to reach a consensus by the December 23 deadline. It deferred the decision to President Biden.

The committee had warned in its final evaluation that Nippon Steel could reduce production in the US. Biden is believed to have determined this would pose a national security risk.

Nippon Steel has argued its plan to protect jobs and maintain production capacity would contribute to strengthening US national security.

Nippon Steel President Imai Tadashi told reporters on December 25 that the company has promised a range of measures to address the concerns.

Imai also said he feels support for the buyout deal is spreading significantly in communities where steel plants are located.