(Reuters) – The two steel groups Nippon Steel and US Steel announced on Monday that they had filed a legal challenge against US President Joe Biden’s decision to block their proposed merger.

Joe Biden decided last week to veto Nippon Steel’s $14.9 billion (€14.37 billion) takeover offer for US Steel, fearing the deal would harm national security.

The two groups believe that the US president’s decision constitutes a violation of the Constitution and are calling for it to be overturned by a federal court.

The merger project, announced a year ago, faced strong opposition in the United States and was a major subject in the 2024 presidential campaign in Pennsylvania, where US Steel is headquartered.

Donald Trump and Joe Biden said the company should remain American-owned, even after Nippon Steel offered to move its U.S. headquarters to Pittsburgh and promised to honor all existing agreements between U.S. Steel and the union USW.

Joe Biden sought to defeat the agreement to “curry favor with USW leaders in Pennsylvania as part of his re-election bid,” Nippon Steel and US Steel said in a statement.

“Due to President Biden’s undue influence to advance his political agenda, the Committee on Foreign Investment in the United States failed to conduct a regulatory review process in good faith focused on national security,” they add. both groups.

A White House spokesperson responded by saying that a committee of national security and trade experts had determined that the acquisition “would create a risk to American national security.”

“President Biden will never hesitate to protect this nation’s security, its infrastructure, and the resilience of its supply chains,” he added.

Nippon Steel and US Steel also filed a complaint against the American steel group Cleveland-Cliffs, its general manager Lourenco Goncalves and the president of the USW union, David McCall, “for their illegal and coordinated actions” aimed at preventing their merger.

David McCall said USW was reviewing the complaint and would “vigorously defend against these baseless allegations.”

The Department of Justice and the US Treasury, as well as Cleveland Cliffs, did not immediately respond to requests for comment.

(Written by Aatreyee Dasgupta in Bangalore; Mara Vîlcu, edited by Blandine Hénault)

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