(Bloomberg) -- Cleveland-Cliffs Inc.’s top executives don’t see any takeover of United States Steel Corp. going ahead without the full support of the United Steelworkers union.

Chief Executive Officer Lourenco Goncalves and his financial chief extended criticisms of Nippon Steel Corp.’s $14.1 billion takeover during the company’s first-quarter earnings call on Tuesday, four months after Cliffs lost its bid to buy US Steel to the Japanese steelmaker.

“It still baffles me to this day that the clueless individuals representing Nippon Steel in this embarrassing event felt that they could do this without union support,” he said. “You just cannot do it with a USW-represented workforce.”

The CEO also said he believes the Biden administration “has different ways to terminate the Nippon transaction, and we believe that will be done sooner rather than later.” 

The White House declined to comment on his remark.

Goncalves told analysts on the call that an earlier proposal to Nippon Steel that would see Cliffs buy US Steel’s union-represented assets while the Japanese company takes the rest is “totally, 100% off the table.”

Nippon Steel agreed to buy US Steel in December, but opposition from the USW and President Joe Biden has left investors uncertain of the deal’s fate. The transaction is subject to a national security review that’s unlikely to conclude until late this year.

Read More: Cliffs’ CEO Calls Share Buybacks Better Use of Money Than Deals

Shares of Cliffs fell as much as 10% Tuesday in New York, its biggest intraday decline since mid-March 2023, after the Cleveland-based steelmaker reported earnings after Monday’s market close that missed analysts’ estimates.

--With assistance from Yvonne Yue Li and Josh Wingrove.

(Updates shares. An earlier version removed incorrect reference on Cliffs’s US Steel interest and clarified quote about proposed solution.)

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