Washington (CNN) White House press secretary Sarah Sanders sought to defend President Donald Trump's credibility -- and her own -- during a lively press briefing Thursday.

Sanders was asked repeatedly about Trump's changing story on the circumstances around a $130,000 hush money payment made to porn actress Stormy Daniels by the President's attorney Michael Cohen over an alleged affair. Trump has denied the affair and previously told reporters he didn't know about the payment. Trump's new lawyer, Rudy Giuliani, told Fox News Wednesday that Trump had reimbursed Cohen for the payment and Thursday morning the President tweeted the money came from the retainer he paid Cohen.

"This was information that the President didn't know at the time but eventually learned," Sanders said about the President's Air Force One claim he didn't know about the payment.

"We give the very best information that we have at the time. I do that every single day," Sanders said when answering a question on why Americans should trust anything the White House says when often it turns out to be untrue.

CNN's Jim Acosta pressed Sanders on whether she was kept in the dark regarding Trump's reimbursement to Cohen. Sanders would not directly respond, only reiterating that she gave the press "the best information that I had."

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