John Kerry: “If Russia were to come in, I tell you Ukrainians, I believe, will fight over the long term.”

It's a matter of mathematics and physics, not politics, not ideology. It is a response to the science.

What we are trying to achieve now is really to establish some stability if we can, in the relationship, without conceding anything.

Nothing is agreed to until everything is agreed to.

There is no current proposal or plan that has been agreed to which would require us to do that.