MSNBC host Lawrence O'Donnell in 2018. (Astrid Stawiarz/Getty Images for Hospital for Special Surgery)

MSNBC host Lawrence O’Donnell on Wednesday retracted a story that alleged that Russian billionaires “close to Vladimir Putin” had co-signed a loan that was given to President Trump by a foreign bank. The brief report, which O’Donnell credited to a single source when it aired Tuesday night, led to the threat of a lawsuit by the president.

On Wednesday, O’Donnell opened “Last Word with Lawrence O’Donnell” by saying his reporting had not gone through the network’s verification and standards process and he was wrong to repeat the allegations on air and for posting it on Twitter.

The previous night, O’Donnell had stressed that the report was unverified, noting that it would be a big deal “if true.” “I have not seen any documentation from Deutsche Bank that supports this and verifies this. This is just a single source who has revealed that to me,” he said.

He later noted that it was not confirmed by news reporters at MSNBC’s parent company, NBC. The next night, he said “saying if true” was “simply not good enough.”

“Tonight we are retracting the story,” he said Wednesday. “We don’t know whether the information is inaccurate but the fact is we do know it wasn’t ready for broadcast and for that I apologize.”

Earlier on Wednesday, Charles Harder, a lawyer for Trump, had sent a letter to NBC demanding that it “immediately and prominently retract, correct and apologize” for the report, which it said was “false and defamatory.”

“The only borrowers under these loans are Trump entities, and Mr. Trump is the only guarantor,” Harder wrote. “Numerous documents for each of these loans are also recorded, publicly available and searchable online. Thus, actual malice can easily be proven based on your reckless disregard of the truth and unreasonable reliance on an alleged “source” who you will not even identify in your story and likely is seeking to mislead you and the public for political reasons or other ulterior motives.”

Trump went on Twitter on Thursday to lash out at O’Donnell.

One of the president’s sons, Eric Trump, had earlier called the report “a reckless attempt to slander our family and smear a great company. Apologies are not enough when the true intent was solely to damage and cause harm. As a company, we will be taking legal action.”

The report came on the heels of the disclosure that Deutsche Bank had some of the personal tax records that Trump has sought so desperately to shield from public view. The records are the subject of multiple inquiries in the House of Representatives.

Trump has sued to try to stop the banks and his accounting firm from complying with congressional subpoenas.

MSNBC did not respond to an immediate request for comment.

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