Two months after Jared Kushner joined the White House as a senior adviser, his family firm sold a stake in a Brooklyn building to a unit of a company whose largest shareholder is the government of Japan.

The buyer of record in the $103-million deal for 175 Pearl St. was Normandy Real Estate Partners, a New Jersey-based investment firm. But documents filed in Tokyo show that it was operating on behalf of a subsidiary of Nippon Telegraph & Telephone Corp. By law, the Japanese government owns at least a third of NTT, in effect a controlling share.

Questions have been raised repeatedly whether Kushner, whose family business has been in search of overseas investors, might pursue a personal agenda while helping run U.S. policy. This is the first known deal with a government-affiliated firm since he entered the White House.