As far as I know, the line of communication between the U.S. and Russia continues to be open and the battlefield commanders are able to communicate with one another. I am aware that there have been certain public statements made out of Moscow.

The increase in the greenhouse gas concentrations in the atmosphere are having an effect. Our ability to predict that effect is very limited.

I think the relationship between the USA and Russia is too important. And it's too important to not find a way to move forward.

I feel it's important that in advising the president, if confirmed, that I deal with facts, that I deal with sufficient information. Which means having access to all information.

I think continued actions by Bashar al-Assad clearly call into any question of him expecting to have any legitimacy to continue as the leader of Syria. With each of those actions, like attack with conventional weapons, barrel bombs and block humanitarian aid he really undermines his own legitimacy.

We're hopeful that Russia will choose to play a constructive role in supporting ceasefires through their own Astana talks, but also, ultimately, through Geneva. And if we can achieve ceasefires in zones of stabilization in Syria, then I believe we will have the conditions to begin a useful political process.

People who speak up for freedom in regimes that are repressive are often at threat.