“There is no doubt the relationship has worsened. He tried again to muck around in our elections this last month,” Mattis said. “We are seeing a continued effort around those lines.”

Mattis said the Trump administration and other NATO allies have pressed Russia repeatedly on un-democratic actions, but to no avail.

“This is a very complex situation because clearly Mr. Putin is a slow learner,” Mattis said. “He is not recognizing that what he is doing is actually creating the animosity against his people.”