Earlier this month, Trump set a 50-day deadline for Russia to accept a ceasefire. Failure to do so, the president said, would prompt punishing new economic measures, among them secondary sanctions on nations doing business with Moscow.

A Russian airstrike on a prison in Ukraine’s southeastern Zaporizhzhia region killed at least 17 inmates and wounded more than 80 others, Ukrainian officials said Tuesday.

It was on July 14 that Trump threatened severe tariffs on Russia if there was no ceasefire agreement within 50 days.