KIEV, Ukraine — A delegation from the International Monetary Fund left Ukraine Friday without announcing a lending agreement, dealing President Volodymyr Zelensky a setback in his efforts to win a quick endorsement from foreign donors for his clean government pledges.

The inconclusive I.M.F. talks coincided Friday with the resignation of the most senior official handling national security in Mr. Zelensky’s administration, reportedly over worries of corrupt influence at senior levels of government.

It wasn’t clear that either development related directly to the center-stage role of the Ukrainian president, a former comedian, in the impeachment inquiry getting underway in the United States Congress. Committees in the House are investigating whether President Trump abused his powers in asking Mr. Zelensky for a political “favor” — an investigation in Ukraine into leading Democrats.

Mr. Trump’s personal lawyer, Rudolph W. Giuliani, had for months pressured members of Mr. Zelensky’s administration to pursue investigations into former Vice President Joseph R. Biden Jr. and his son Hunter Biden, who was on the board of an energy company owned by a Ukrainian oligarch.