There are numerous threats to members of the North Atlantic Treaty Organization alliance, President Barack Obama said in a news conference today, and it will work together to take action on those threats.
Obama said the central mission of the NATO alliance is a duty to support each other, and an armed attack against one should be considered an attack against all.
"Russia must stop its violations" against Ukraine, Obama said. "We will defend every ally," including Ukraine.
A Ukrainian cease-fire reached and announced today will work "only if there is follow-through on the ground," he said.
To ensure NATO remains ready, the alliance will update its defense planning and create a rapid response force that will be deployed on a moment's notice, Obama said.
The alliance will provide security assistance to Ukraine and help modernize Ukrainian forces, including logistics and command and control.
Key NATO allies also stand ready to defend against threats posed by ISIS in Syria and Iraq, Obama said.
"I will continue to do what is necessary to defend the American people, and [ISIS] poses a real threat," he said.
With regard to conflict in Syria, American troops will not be placed on the ground there, Obama said.