WASHINGTON, March 26 (Reuters) - The White House is investigating whether two loans totaling more than $500 million to the family real estate business of U.S. President Donald Trump’s son-in-law and senior adviser Jared Kushner violated any criminal laws or regulations, according to the U.S. Office of Government Ethics.

Democratic lawmakers asked the White House and Kushner Cos for documents after the New York Times last month reported the loans extended in 2017 by Citigroup Inc and the private equity firm Apollo Global Management.

In a letter to a congressman made public on Monday, David Apol, acting director and general counsel of the Office of Government Ethics, said, "I have discussed this matter with the White House Counsel's Office in order to ensure that they have begun the process of ascertaining the facts necessary to determine whether any law or regulation has been violated."

"During that discussion, the White House informed me that they had already begun this process," Apol said in the letter dated March 22 to Democratic Representative Raja Krishnamoorthi.

Kushner's lawyer Abbe Lowell and the White House did not immediately respond to requests for comment.

The New York Times reported in February that Citigroup lent Kushner Cos and one of its partners $325 million in the spring of 2017 shortly after Citigroup’s chief executive, Michael Corbat, met with Kushner in the White House.

It said Joshua Harris, a founder of Apollo, was advising Trump administration officials on infrastructure policy and held several meetings with Kushner, and Apollo lent $184 million to Kushner Cos in November.

In a letter to Apol, Krishnamoorthi had said that if the Times report was accurate, it would raise serious ethical questions, and asked whether Kushner's actions "constitute a breach of his ethical obligations to the American people."

Last year Kushner, who is married to Trump’s daughter Ivanka Trump, resigned from Kushner Cos and sold his stake in a family trust as part of an effort to avoid conflicts of interests in his White House role. The private real estate company owns or partially owns buildings in New York and New Jersey. (Reporting by Mark Hosenball Additional reporting by Eric Walsh Writing by Mohammad Zargham Editing by Toni Reinhold)