Ukraine’s president said Wednesday that Russia must pull back to its pre-war positions as a first step before diplomatic talks, a negotiating line that Moscow is unlikely to agree to anytime soon. President Volodymyr Zelenskyy said he currently sees no willingness on the part of Russia to resume earnest negotiations on ending the three-month war. “At the beginning, there was an impression that we can move ahead, that there would be a certain result or some outcome of those talks. But it all has stalled,” Zelenskyy said through an interpreter by video link to attendees at this year’s World Economic...