This is the first time the president has commented publicly on the issue. "Michael's my attorney, and you'll have to ask Michael".
Trump said he did not know why Cohen made the payment.
"You'll have to ask Michael Cohen", he said.
Asked aboard Air Force One whether he knew about the payment, Mr Trump responded "no".
Cohen and the White House have said that Trump denies the affair, and that Trump was unaware of the payment, which Cohen said he made from his own pocket.
"Trump's denial of any knowledge of the payment could help Stormy Daniels's argument that her NDA is invalid, according to legal experts who say the contract language require's Trump assent", Balhaus wrote.
Daniels' attorney, Michael Avenatti, said Thursday his client's case "just got that much better" with the president's on-the-record comments.
Daniels is suing Cohen to be released from the agreement, which she says Trump didn't sign.
On Thursday, NBC News tweeted this clip of a reporter asking Trump about the scandal on Air Force One, and amazingly, Trump answered a few questions. "As history teaches us, it is one thing to deceive the press and quite another to do so under oath". She also claims that Trump and Cohen have defamed her by suggesting she's lying about the affair.
Trump has until now avoided questions about Daniels, who claims he and Trump had sex once in 2006, as part of a 10-month affair when she was 26.