More than five hours of talks at the Kremlin between Russian President Vladimir Putin and the leaders of France and Germany yielded no deal to end the fighting in eastern Ukraine. But the three agreed to continue diplomacy in hopes of clinching a long-awaited cease-fire within days.

German Chancellor Angela Merkel and French President François Hollande went to Moscow after violence flared anew in the region, and as Washington considers providing weapons to Kiev to try to counter further aggression by Russia-backed separatist...