Putin Reportedly Says Russia Could ‘Take Kiev in 2 Weeks’

President Vladimir V. Putin of Russia reportedly told a European official that he could “take Kiev in two weeks” if he wanted to, adding a new dimension to the tensions building in Ukraine as Russian forces become more involved in the fighting there.

As NATO leaders gather in Wales for a summit meeting, Mr. Putin’s remarks and the increasing presence of Russian military units in Ukraine have posed a stark new challenge to the alliance about how to respond to Moscow’s apparent willingness to exert military force to achieve its...