(CNN) Donald Trump will hold a news conference Tuesday to provide a full accounting of a veterans' fundraiser in January, the presumptive Republican nominee said Sunday.

Trump said repeatedly that the fundraiser, held in lieu of Trump participating in a Fox News Republican presidential debate, raised $6 million dollars for veteran's causes. But the Trump campaign has been dogged by reporters demanding to know exactly how much was raised and where the money was being sent.

"We just raised almost $6 million for the vets because I didn't do a television show," Trump said in Washington, D.C., at the annual Rolling Thunder rally to honor U.S. prisoners of war and missing-in-action troops. "All of the groups that have gotten the money will be announced on Tuesday."

After months of inquiries, Trump himself called CNN Thursday to explain that some of the bigger donors "had to be reminded of their pledge." Trump said it was perfectly understandable since the donors were "very busy people, some even located overseas." But Trump did confirm to CNN that the final number would be "close to" the $6 million dollar figure Trump announced shortly after the January fundraiser.

CNN determined Wednesday that Trump personally donated $1 million dollars to the Marine Corps Law Enforcement Foundation, an organization dedicated to supporting the children of fallen Marines and Federal Law Enforcement officers. "We did receive the check this morning and deposited it locally," said a spokesman for the charity.

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