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US Steel and Nippon Steel filed a lawsuit Monday against the US government, claiming the deal was only blocked for political reasons.
New York CNN  — 

President Joe Biden decided to block the $14 billion takeover of US Steel by Japan’s Nippon Steel even though some top US officials did not believe there were sufficient national security grounds to kill the deal, a US official told CNN.

The controversial decision to block the US Steel deal has won praise from union officials but faced fierce criticism inside and outside the administration.

US Steel and Nippon Steel alleged in a Monday lawsuit that the process was driven by politics, not national security concerns.

Even though the US Steel takeover offer was from a company based in Japan – a major US ally – like all foreign acquisitions, it faced an intense review from the Committee on Foreign Investment in the United States (CFIUS), a powerful but secretive interagency panel.

However, CFIUS failed to reach a decision about whether the deal posed a national security risk, leaving the decision to the president.

Multiple prominent CFIUS members believed that any national security risk could be mitigated and that there were insufficient grounds to block the deal, including Treasury Secretary Janet Yellen, Defense Secretary Lloyd Austin and Secretary of State Antony Blinken, the US official said.

The presence of those officials in the camp against blocking the deal is notable because Yellen chairs CFIUS and Austin would have insight into whether the US defense industrial base would be threatened by this proposed foreign takeover.

However, other CFIUS members were opposed on national security grounds, including US Trade Representative Katherine Tai, two sources familiar with the CFIUS process told CNN. Officials at the US Energy Department and Commerce Department also had concerns about the deal, one of the sources said.

The Department of Defense referred CNN to the White House. None of the US agencies involved in CFIUS’s decision would comment to CNN on the private deliberations.

Biden specifically cited national security and the importance of a strong domestic steel industry in his statement explaining the decision on Friday.

“This acquisition would place one of America’s largest steel producers under foreign control and create risk for our national security and our critical supply chains,” Biden said.

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A man in a crane charges slabs of iron at the Gary Works plant in Gary, Indiana, in 1945. Gary Works, US Steel's largest manufacturing plant, was the largest steel mill in the world for most of the 20th century, according to the Chicago Sun-Times.
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A group of workers from US Steel attend an English class in Pittsburgh in 1913. The Pittsburgh-based company formed in 1901 as a merger of the nation's leading steel companies, including Carnegie Steel Corp.
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Workers strike outside the US Steel plant in Gary, Indiana, in 1919.
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An open hearth furnace is seen at a US Steel plant in Duquesne, Pennsylvania, in 1936.
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The San Francisco-Oakland Bay Bridge is constructed in California in 1936. It is one of many famous structures that US Steel supplied steel for and erected.
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During World War II, US Steel played a critical role in the Allied forces' war efforts. Here, Irma Engstom operates a punch machine in Gary, Indiana, that cut steel discs for 75mm shell cases.
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An electric furnace is tilted to pour 40 tons of stainless steel at a plant in Pennsylvania in 1945.
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Striking steelworkers picket in Homestead, Pennsylvania, in 1946. An estimated 750,000 workers took part in the walkout, shutting down 1,200 plants in 30 states.
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US War Secretary Robert P. Patterson, left, congratulates US Steel President Benjamin Fairless after he was awarded the Medal of Merit in 1946. At right is Gen. Dwight D. Eisenhower, who would later become president.
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At left, steel beams for the United Nations Secretariat Building are loaded at a US Steel plant in Munhall, Pennsylvania, in 1948. On the right, a woman knits from a fire escape in New York as the Secretariat Building is under construction.
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Workers wash off pulverized coal before forging a steel plate at a plant in South Charleston, West Virginia, in 1950.
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A temporary television antenna is adjusted atop New York's Empire State Building by a worker from US Steel's American Bridge Co. in 1950.
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A US Steel worker poses for a portrait circa 1951.
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A worker oversees pipe production at a plant in Fairless Hills, Pennsylvania, circa 1955.
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New twin blast furnaces operate at US Steel's South Chicago Works in 1956. They were among the world's largest at the time, standing 235 feet tall.
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A tavern sign tries to entice striking steelworkers in Chicago in 1959.
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Workers toil around the clock to complete the installation of the main support cables of the Verrazzano-Narrows Bridge in New York in 1963.
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Men work at the Homestead Steel Works factory in Homestead, Pennsylvania, circa 1970. From its peak in the 1950s, the company began to fall behind upstart competitors both foreign and domestic. Competitors in Japan and Germany, which were forced to rebuild from scratch after World War II, used new technologies that required far less labor and energy.
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A helicopter lifts a panel of steel over the Louisiana Superdome that was being built in New Orleans in 1973.
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A worker helps construct the top floors of the Sears Tower building in Chicago in 1973.
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Bob Simmons monitors controls for a furnace and rolling machine at a US Steel research and development facility in Monroeville, Pennsylvania, in 2005.
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A man arrives at a US Steel plant in Clairton, Pennsylvania, in 2018. In recent years, US Steel has fallen far below other American steel companies in steel output and stock market value.
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President Donald Trump speaks to steelworkers in Granite City, Illinois, in 2018. Trump's administration imposed a 25% tariff on steel imports and 10% tariff on aluminum to shore up the struggling industries.
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Steelworker Amanda Menendez watches the steel production process from office monitors in Granite City, Illinois, in 2018.
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The US Steel plant in Clairton, Pennsylvania, is seen along the banks of the Monongahela River in 2023.

The Washington Post and Wall Street Journal previously reported that Biden rejected appeals of several top advisers in deciding to tank the deal.

“Bad decision,” one senior administration official told CNN’s Kayla Tausche. “Doesn’t actually protect union jobs and may kill the company.”

Another US official told CNN that there are significant frustrations among Biden officials about how the process played out and concerns about the signal it sends about foreign direct investment in the United States.

After all, this foreign takeover was not from a rival nation such as China or Russia, it was from longtime US ally Japan.

“Never before has a President prohibited an acquisition by a company based in Japan, one of our closest allies,” US Steel and Nippon Steel argued in the lawsuit.

Jason Furman, a top economic official during the Obama administration, blasted the decision to use national security to kill the deal.

“President Biden claiming Japan’s investment in an American steel company is a threat to national security is a pathetic and craven cave to special interests that will make America less prosperous and safe,” Furman, who is now a professor at Harvard University and a senior adviser at an Asia-focused consulting firm, wrote in an X post on Friday. “I’m sorry to see him betraying our allies while abusing the law.”

The White House defended the decision in a statement on Monday in response to the lawsuit filed by US Steel and Nippon Steel.

“A committee of national security and trade experts determined this acquisition would create risk for American national security,” White House spokesperson Robyn Patterson said in a statement. “President Biden will never hesitate to protect the security of this nation, its infrastructure, and the resilience of its supply chains.”

Michael Leiter, who leads the CFIUS and national security practices at law firm Skadden, told CNN in an email that the disagreement among US agencies shows how, like many national security issues, “this wasn’t an easy issue, and there were competing interests.”

“The presence and sufficiency of national security risk is in the eye of the beholder—and under CFIUS the only eye that matters is the President’s,” he said.

Leiter does not believe the US Steel deal will ultimately hurt foreign investment into the United States, the world’s largest economy.

“For those of us who handle billions of dollars of transactions a year,” he said, “we know that this was an outlier. This case will neither have significant precedential value, nor will it so poison the CFIUS well.”

Opposition to the US Steel takeover was bipartisan, including multiple Rust Belt lawmakers from both sides of the aisle.

Both Vice President Kamala Harris and President-elect Donald Trump opposed the deal during the presidential campaign, as did Vice President-elect JD Vance.

Union officials praised Biden’s decision to block the merger.

“We have no doubt that it’s the right move for our members and our national security,” United Steelworkers International President David McCall said in a statement.