WASHINGTON — Felix H. Sater, a former business associate of President Trump’s, failed to show up on Friday to an interview with House investigators meant to explore his work on a proposed Trump real estate project in Moscow. He will now face a congressional subpoena.

Mr. Sater had voluntarily agreed to appear privately before the House Intelligence Committee and touted his cooperation to news outlets in recent days, pledging to “answer every question without exception.” His testimony was expected to inform the Democrat-led panel’s continuing investigation into whether Russia or other foreign powers have publicly unknown leverage — financial or otherwise — over Mr. Trump or his associates.

But on Friday morning, after committee staff had already gathered in the Capitol, Mr. Sater’s lawyer, Robert S. Wolf, said that he was unable to attend “due to health reasons,” but was willing to reschedule.

The abrupt change displeased Representative Adam B. Schiff, Democrat of California and the committee’s chairman. He said a subpoena compelling Mr. Sater’s appearance was “fairly imminent.”