New York Mayor Bill de Blasio said Friday that the city —"because of the possibility of a criminal act" — notified Manhattan prosecutors after news reports that the Trump Organization gave conflicting information about income and expenses to city tax officials and investors.

"This is a real problem, and I think there could be some real exposure here," de Blasio told WNYC when a reporter asked if the city had conducted an inquiry into the reports, by that radio station and ProPublica, of discrepancies in how President Donald Trump's company reported financial information to different entities.

"It was looked at [by the city] and one of the specific issues within your story — or ProPublica story originally — was referred to the district attorney because there is the possibility of a criminal act having been committed," said de Blasio, who until September had sought the Democratic nomination for president in 2020.

ProPublica and WNYC reported in October that documents showed that Trump's businesses gave lenders and New York City tax authorities "different figures" for "some expenses, profits and occupancy figures for two Manhattan buildings."

"The discrepancies made the buildings appear more profitable to the lender — and less profitable to the officials who set the buildings' property tax," the news site noted.

Nancy Wallace, a professor of finance and real estate at the Haas School of Business at the University of California, Berkeley, told ProPublica that such discrepancies are "versions of fraud."

"This kind of stuff is not OK," Wallace said.

"Certainly, if I were sitting in a prosecutor's office, I would want to ask a lot more questions," said Anne Milgram, a former attorney general for New Jersey who is now a professor at New York University School of Law, in an interview with the news outlets.

A spokeswoman for de Blasio later told CNBC that city made the referral to the Manhattan District Attorney's Office in November on the heels of the reports by ProPublica and WNYC.

"ProPublica and WNYC's investigation raised questions about what was reported to the Tax Commission versus bank lenders," said Laura Feyer, the spokeswoman.

"The Manhattan DA is the proper jurisdiction to investigate these claims, as the City can only review what is directly reported to us. The DA has the jurisdiction to take appropriate steps if they find wrongdoing."

Danny Frost, a spokesman for Manhattan DA Cyrus Vance Jr. told CNBC, "We will decline to comment."

"Our office does not confirm investigations," Frost said.

A spokeswoman for the Trump Organization, when asked about de Blasio's comments, told CNBC, "Given the rash of investigations launched against the mayor's presidential campaign and administration, he is the last person to be pointing fingers."

"But even more troubling is his admission that, at or around the time he was running for president, he was using the power of his office to try and launch an investigation into his political opponent," the spokeswoman said. "The allegations are unfounded and clearly motivated by politics."

After this story was first published, de Blasio's press office in an email to CNBC said the comment from the Trump Organization was inaccurate because the mayor no longer was running for president at the time of the reports about discrepancies in financial statements by the company, much less at the time the city made its referral to Vance's office.

Freddi Goldstein, de Blasio's press secretary, said in that email, "President Trump is a con-artist and his refusal to release his tax returns says more than enough about what he is trying to hide."

Trump, unlike all other presidents in the past four decades, has refused to release his income tax returns publicly.

Vance's office is seeking eight years of Trump's personal and corporate tax returns from his longtime accountants through a state grand jury as part of an ongoing criminal inquiry into the Trump Organization.

A federal judge and appeals court refused Trump's requests to block that subpoena, rejecting arguments by his lawyer that a president is immune from criminal investigation, much less criminal prosecution, while serving in the White House.

The U.S. Supreme Court in December said it would hear Trump's appeal of those decisions, as well as two other cases in which he is trying to block demands for his taxes and other financial records from two House committees controlled by Democrats.

The cases will be argued this year before the high court.