The race to become the next leader of the United Nations moved into a higher gear with the four declared candidates facing hours of questions over two days. Top among them: can the U.N. be made effective again?

Rafael Mariano Grossi, an Argentine diplomat who heads the International Atomic Energy Agency, struck a downbeat note about the global body’s future during his interview to replace Secretary-General Antonio Guterres.

“This election, or selection, process is so consequential, and this is because we are at a time when there are enormous, huge doubts about our institution,” Grossi said on Tuesday. “The direction in which the U.N. is moving is not the one we would all like to see.”