Putin’s refusal to compromise on Ukraine, analysts say, is a colossal error costing Russia regional influence, lucrative energy markets and its place in the world.

US President Donald Trump’s 50-day pause ahead of possible secondary sanctions on Russia gifts the Kremlin a window to exploit the incremental gains of recent weeks, which analysts say increasingly pu...

If Trump now permits a substantial amount of U.S. weapons to continue to flow to Ukraine, that would mark an important change. Since Trump took office, many in Ukraine and European capitals have thought that might well be the best-case scenario for Ukraine, given the U.S. president's clear hostility to continuing U.S. donations.

Trump announced Monday that the U.S. will be sending weapons to Ukraine through NATO, marking a turnaround from previous policy that was generally skeptical of supplying Kiev with weapons while the U...