MSNBC host Lawrence O’Donnell on Wednesday walked back allegations made during a segment of his Tuesday evening broadcast after lawyers for President Donald Trump demanded an apology and retraction.

At the top of The Last Word with Lawrence O’Donnell, the eponymous host claimed that “a single source close to Deutsche Bank” told him that loan documents with the bank revealed that Trump had co-signers that are “Russian oligarchs” close to Russian President Vladimir Putin.

“These statements are false and defamatory, and extremely damaging. The only borrowers under these loans are Trump entities, and Mr. Trump is the only guarantor,” attorney Charles Harder wrote in a letter sent to NBC Universal’s counsel. “Demand is hereby made that Mr. O’Donnell and NBCU immediately and prominently retract, correct and apologize for the aforementioned false and defamatory statements.”

NBC News noted on Wednesday morning that O’Donnell’s information came from “a single source who has not seen the bank records” and since the network has not seen the records, they have “not yet been able to verify the reporting.”

Shortly after Trump's lawyer issued the demand letter, O'Donnell took to Twitter to issue an apology for the “error in judgment,” adding that it was “wrong to discuss it on the air” and he’ll address this in full on his Wednesday night program.