On a trip to Estonia, President Obama placed blame on Russian separatists for destabilizing eastern Ukraine. He also pledged support for the U.S.’ NATO allies. Meanwhile, reports surfaced of a potential cease-fire agreement in Ukraine. Margaret Warner reports.

Sep 03

Obama: Russia threatens peace in Europe

Obama, who faces criticism in the U.S. for being too cautious in confronting Russian President Putin, sharply condemned Moscow's provocations. He declared in blunt terms that Russian forces that have moved into Ukraine in recent weeks are not on a…

Sep 02

NATO to bolster security against Russian aggression

Confronted by a Kremlin-backed military offensive in Ukraine, President Barack Obama and Western allies will approve plans this week to position at least 4,000 troops and military equipment in Eastern Europe, bolstering NATO's security commitments to nervous member states near…

Aug 29

NATO: very much alive at 65

When the leaders of the North Atlantic alliance wrapped up their Chicago summit two years ago and started preparing for their 65th anniversary meeting in 2014, they could have asked John Travolta to provide the soundtrack, "Stayin' Alive."…

Ukraine claims Russian forces are on Ukrainian soil, and are helping rebels open a new front in the southeast. Kiev confirmed the rebels have captured the town of Novoazovsk, leaving the port city of Mariupol vulnerable to attack. At the…