NEW YORK (AP) — MSNBC’s Lawrence O’Donnell says he made an “error in judgment” in reporting a story about President Donald Trump’s finances based on a single source.

O’Donnell’s tweet on Wednesday came after a lawyer for Trump said the story was false and defamatory, and called for NBC News to apologize and retract it.

The MSNBC host said Tuesday he had been told that Deutsche Bank has documents showing that Russian oligarchs had co-signed loans for Trump.

O’Donnell said on his show that if this were true, it would explain every kind word Donald Trump has ever said about Russia and its leader Vladimir Putin. O’Donnell didn’t identify his source and said, even as he reported it, that NBC News has not verified the accuracy of the story.

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