"It is good ... the president came clean about this liability on this year's form, but we now have to wonder how many other liabilities for similar payments he has that he still has not disclosed", CREW Executive Director Noah Bookbinder said in a statement.
Trump had earlier denied knowledge of such a payment.
The ethics office's acting director wrote Deputy Attorney General Rod Rosenstein saying this latest report may be "relevant" if the DOJ is investigating the president's filing from a year ago.
"... You may find the disclosure relevant to any inquiry you may be pursuing regarding the President's prior report that was signed on June 14, 2017", Apol wrote.
The ethics office is a government watchdog that provides oversight of the executive branch program created to prevent and resolve conflicts of interest.
"Mr. Cohen sought reimbursement of those expenses and Mr. Trump fully reimbursed Mr. Cohen in 2017", the report states.
The OGE told the Justice Department in a letter released Wednesday, CNBC reported, that Cohen's payment to a third-party should legally have been detailed in the president's 2016 financial disclosure filing.
Cohen previously insisted that he paid the money out of his own pocket and Trump was not involved.
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Even the much-hyped Wayne Rooney, despite his stellar record at Manchester United over the years, failed to breach that mark. Goalkeepers: Jack Butland ( Stoke City ), Jordan Pickford ( Everton ), Nick Pope ( Burnley ).
Apol was referencing a complaint from Citizens for Responsibility and Ethics in Washington (CREW), a left-leaning watchdog group.
Daniels, whose real name is Stephanie Clifford, claims she had a tryst with Trump in 2006 while he was married. The amount paid to Daniels, through Cohen, was said to be $130,000 - related to her claim of an affair with Trump before he was president. The agency reviewed the form and made it public on Wednesday.
Michael Cohen, Trump's personal lawyer, is under criminal investigation for his business dealings.
Trump then acknowledged, via Twitter, the substance of Giuliani's assertion, which prompted 48 hours of contradictory follow-ups by both Giuliani and the White House about what Trump knew and when he might have known it, about any payments.
The ethics disclosure also contained information on Trump's personal businesses.
For the 15 ½-month time period in the previous report, $115.9 million in revenue was generated by Trump National Doral Golf Club, $37.3 million by Mar-a-Lago, $20.1 million by Trump National Golf Club in Jupiter and $18.4 million by Trump International Golf Club in West Palm Beach.
Trump has at least $315 million in debt, about the same as he reported a year ago. It also provides much less specificity than his tax returns, which he has refused to make public. President Trump can take back control of the trust at any time and he's allowed to withdraw cash from it as he pleases.