President Trump is used to world leaders bowing down to him, and to cabinet members fawning over him. Jerome H. Powell, the chair of the Federal Reserve, took a different approach.

President Trump’s special envoy said that “we will now consider alternative options to bring the hostages home,” though it was not clear that negotiations had halted.

The deal, which came under intense scrutiny by the Trump administration, was hailed by the F.C.C. chief, who welcomed “significant changes” at CBS, a unit of Paramount.