Russian President Vladimir Putin recognised two breakaway regions in eastern Ukraine as independent on Monday and ordered the Russian army to launch what Moscow called a peacekeeping operation into the area, accelerating a crisis the West fears could unleash a major war.

Putin told Russia's defence ministry to deploy troops into the two regions to "keep the peace" in a decree issued shortly after announcing recognition for Russian-backed separatists there, drawing US and European condemnation and vows of new sanctions...