New York state has asked three banks to supply information about their relationships with the real estate business of Jared Kushner, a senior White House advisor and President Donald Trump's son-in-law, a source said Wednesday.

Maria Vullo, Superintendent of the Department of Financial Services (DFS), sent letters last week to Deutsche Bank, Signature Bank and New York Community Bank asking for details on their financial arrangements as well as loans made to or sought by Kushner Companies, the source told AFP.

The lenders were given until March 5 to respond.

The DFS has refused to comment on the matter, as has Deutsche Bank.

But Kushner Companies said the inquiries were politically motivated and amounted to harassment.

"We have not received a copy of any letter from the New York State Department of Financial Services," a spokesman said.

"Our company is a multi-billion enterprise that is extremely financially strong. Prior to our CEO voluntarily resigning to serve our country, we never had any type of inquiries.

"These type of inquiries appear to be harassment solely for political reasons."

Conflicts of interest?

Also on Wednesday, The New York Times reported Kushner Companies received major loans from Apollo Global Management, one of the world's largest private equity firms, and Citigroup, shortly after Kushner held White House meetings with representatives from the two companies.

The paper quoted Don Fox, the former acting director of the Office of Government Ethics during the Obama administration, as saying the loans raised questions about the appearance of conflicts of interest.

Kusher met Joshua Harris, a founder of Apollo, multiple times over the course of 2017 and even discussed a potential White House position which never materialized, the paper said.

In November 2017, the firm loaned Kushner Companies $184 million -- triple the size of its average property loan.

He also met Citigroup's chief executive in the spring of 2017, Michael L. Corbat, shortly before Kushner Companies received a $325 million loan from the firm, the Times reported.

The White House referred questions to Mr. Kushner's lawyer, Abbe Lowell, whom the paper said did not dispute that the meetings took place, but denied any impropriety.

Kushner, who is married to the president's daughter Ivanka Trump, has been a key figure in the administration of his father-in-law, entrusted among other things with finding a peace deal between Israelis and Palestinians.

A Harvard graduate with a law degree from New York University, Kushner took the reins of his family business before announcing in January 2017 -- just ahead of his appointment to the Trump administration -- that he was stepping down from his management role.

While Jared Kushner voluntarily left high-level positions in more than 200 entities related to his family's real estate empire, he still retains shares in most of these companies from which he is likely able to derive income, according to documents published by the White House in April 2017.

It is not the first time Kushner's business interests, which include real estate assets in the states of New York and New Jersey, have been in the spotlight.

In May 2017, the company was forced to apologize for mentioning Jared Kushner during a presentation of one of its projects to a group of Chinese investors, in a possible breach of conflict of interest rules.