The House committee said on Thursday that it was investigating whether former President Donald J. Trump's son-in-law and former adviser traded on his government position to land a $2 billion investment in his new private equity firm.

The New York Democrat who leads the House Committee on Oversight and Reform gave the president's son-in-law a two week deadline to provide documents related to the Saudi fund's investment. During or after the Trump administration, she asked for any personal correspondence between the president's son-in-law and the crown prince of Saudi Arabia.

The committee is looking into whether your personal financial interests influenced U.S. foreign policy during the administration of your father-in-law.

A spokesman for Mr. Kushner said that he followed all legal and ethical guidelines during and after his government service.

The statement said that he was proud to be among many private sector stakeholders who were working to encourage continued regional progress.

The Saudi government and the Saudi Public Investment Fund didn't respond to requests for comment.

Representative Jerrold Nadler, a fellow Democrat from the Upper West Side, faces a tough primary challenge from Ms. Maloney, a veteran lawmaker from the Upper East Side. Mr. Nadler is a critic of the Trump administration.

The Saudi government's main wealth fund invested $2 billion in Mr. Kushner's firm despite objections from one of its own internal committees. Less than six months after he left the White House, that investment took place.

Even though Prince Mohammed faced criticism over his human rights record, Mr. Kushner developed a close relationship with him. The board of the Public Investment Fund voted to approve the $2 billion investment even though they were skeptical.

The Saudi fund's investment in Mr. Kushner's firm appears to be the majority of its assets. The Justice Department has been urged by Senator Elizabeth Warren to take a hard look at the situation.

The letter was dated Tuesday and was written by Ms. Maloney. The appearance of your new business venture will be created by your close relationship with Crown Prince bin Salman, your pro-Saudi positions during the Trump administration, and PIF's decision to fund the lion's share of your new business venture.

The investigation would seek to gather information about whether stricter laws are needed to prevent former public officials from doing business with their previous government counterparts.

Both the Trump administration and Saudi Arabia have been examined by the House Oversight Committee. The administration's willingness to share nuclear-power technology with the kingdom was the subject of a report.