The United States and NATO will not abandon their allies in Europe, that are concerned about Russian aggression.
The US President Barack Obama said that while delivering a speech at the 95th National Convention of Disabled American Veterans.
"In the face of Russian aggression, we're not going to turn our back to our allies in Europe. We're going to stay united in Nato, which is the world's strongest alliance", Obama said.
His speech arrived after a statement made earlier by Donald Trump, the Republican Party nominee for the US President.
In an interview with The New York Times Trump said, if Russia attacked NATO allies in Europe, he would decide to help only after reviewing if those nations "had fulfilled their obligations".