Cable news host Lawrence O’Donnell was forced to admit he was wrong to claim that Russian moguls close to Vladimir Putin had co-signed huge bank loans to Donald Trump before he became president.

The mea culpa from the MSNBC host came after the president’s lawyer threatened to sue O’Donnell and the network for defamation.

“Last night I made an error in judgment by reporting an item about the president’s finances that didn’t go through our rigorous verification and standards process. I shouldn’t have reported it and I was wrong to discuss it on the air. I will address the issue on my show tonight,” O’Donnell, who hosts “Last Word,” said on Twitter Wednesday.

And indeed, as he went on the air, he apologized again, saying his reporting had been “simply not good enough.”

He continued, “Tonight we are retracting the story. 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.”

He had tweeted out the erroneous report, writing, “A source close to Deutsche Bank says Trump’s tax returns show he pays very little income tax and, more importantly, that his loans have Russian co-signers. If true, that explains every kind word Trump has ever said about Russia and Putin.”

O’Donnell walked back the claim after Trump’s personal lawyer Charles Harder demanded a retraction and an apology, which was reported by Deadline.com.

“These statements are false and defamatory, and extremely damaging,” Harder — who won Hulk Hogan millions of dollars in his sex tape case against the former Gawker website — said in a letter Wednesday to NBC Universal’s executive vice president and General Counsel Susan Weiner and SVP for Litigation Daniel Kummer over O’Donnell’s report.

“The only borrowers under these loans are Trump entities, and Mr. Trump is the only guarantor,” Harder added in the two-page letter. “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.”