Washington (CNN) The attorney for porn star Stormy Daniels, who's suing President Donald Trump, said Friday that the American people need to hear from his client "because cover-ups matter."

Daniels, whose legal name is Stephanie Clifford, filed suit against Trump on Tuesday, alleging that he never signed a hush agreement regarding an alleged sexual encounter between the two and therefore the agreement is void.

White House press secretary Sarah Sanders said Wednesday that "arbitration was won in the President's favor" regarding the case. The statement is an admission that the nondisclosure agreement exists and that it directly involves Trump. It was the first time the White House had admitted the President was involved in any way with Clifford.

Trump's personal lawyer, Michael Cohen, said last month that he paid $130,000 of his own money to Clifford right before the 2016 election in exchange for her silence about the matter. But both Cohen and the White House have denied any sexual encounter between the President and Clifford.

"The cover-up is that you have attorney (Michael) Cohen claiming that Donald Trump never knew anything about this. You have the White House claiming Donald Trump never knew anything about this. That is going to be shown to be patently false," Michael Avenatti, the attorney for Daniels, said in an interview Friday on CNN's "New Day."

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