(CNN) Donald Trump's fresh acknowledgment this week that he reimbursed his lawyer Michael Cohen more than $100,000 in 2017 is raising red flags with ethics experts about why the President withheld information from the public about those payments last year.

Trump's financial disclosure report released on Wednesday -- covering all of 2017-- stated the President paid Cohen back last year between $100,001 and $250,000 for various expenses Cohen incurred while working for Trump.

"Mr. Cohen sought reimbursement of those expenses and Mr. Trump fully reimbursed Mr. Cohen in 2017," the disclosure said.

While Wednesday's disclosure did not specify what Cohen was being reimbursed for, he paid porn star Stormy Daniels $130,000 in October 2016 as a part of a hush agreement to keep the porn star quiet about her alleged affair with Trump.

That revelation has brought to stark focus the reality that Trump's previous financial disclosure report released last June -- which covered all of 2016 through mid-April 2017 -- made no mention of Trump's payments to Cohen, despite the fact that Rudy Giuliani, Trump's lawyer, recently said that Trump's monthly payments to Cohen began in early 2017.

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