Donald Trump Claims He's Sold All of His Stocks Without Offering Proof

— -- Donald Trump announced Wednesday that he sold all of his stock holdings a few months ago. But the president-elect has never offered proof that such a sale happened.

This declaration comes amid continued questions about his potential conflicts of interest once he assumes office.

Mark Zandi, the chief economist for Moody’s Analytics, told ABC News that there’s no way to check if Trump actually sold his stock investments.

“There’s no transparency, so how do we know one way or another?” Zandi said.

On Dec. 2 Trump spokeswoman Hope Hicks told The Associated Press that it was “her understanding that Trump recently sold his Energy Transfer stock but provided no details.” Energy Transfer is one of the companies involved in the construction of the controversial Dakota Access Pipeline.

On Tuesday, another Trump spokesman, Jason Miller, told reporters that Trump had sold all of his stocks in June, and Trump himself reiterated that claim.

“I was never a big stockholder, but I bought a lot of different stocks and I had a lot of stock before then too, and what I did is I sold them. I don't think it's appropriate for me to be owning stocks when I'm making deals for this country that maybe will affect one company positively and one company negatively,” Trump said on “The Today Show” Wednesday morning.

In August, Trump told Fox Business that he “got out” of the stock market but did not mention any concerns about potential conflicts of interest.

“I did invest and I got out and it was actually very good timing,” Trump said on Aug. 2 without specifying when exactly he sold his stocks.

The extent of Trump’s prior stock holdings is not completely known and is based on his personal financial disclosure form that reflected his investments as of this past May.

The 104-page document shows that Trump had investments in companies like Energy Transfer and Phillips 66, both of which have ties to the Dakota Access Pipeline. The disclosure also showed that Trump had investments in Boeing and United Technologies, the parent company of Carrier, two companies that he has gotten into public tangles with in recent days.

John Hudak, a political scientist and senior fellow at the Washington-based Brookings Institution, said that “it’s really hard for me to believe” that Trump sold all of his stocks months ago and is only broaching the topic now.

“There is not much that Trump does that is significant that he does not brag about or make very public, so I would think given all of the concerns about his conflicts of interest and his taxes and his finances, that if he did take that step, that he would have been very public about it,” Hudak told ABC News.

Hudak said that one possible explanation for why Trump may not have announced his stock sale sooner is “because if he was then pressed for documentation of it, he would have then revealed at least in part the size of his investment portfolio.”

Trump did not release his tax returns during the campaign, making him the first presidential candidate in four decades not to do so.

ABC News has asked for further details about Trump’s stock holdings and has not heard back from his transition team.