are trying to free the city from isis control. this weekend defense secretary ash carter flew to iraq to assess the battle. >> nothing that i take more seriously than putting americans in arm's way. make no mistake whether they're flying airplanes overhead or advising units on the ground, even behind the front lines, they are at risk. it's also important that everybody understands that we must do this. >> let's bring in cnn pentagon correspondent barbara starr and cnn international anchor and correspondent michael holmes who is near mosul. michael, let me start with you. what is the situation in and around mosul this morning? >> yeah, as you know, alisyn, the iraqis and the kurdish peshmerga are trying to encircle mosul before they can think about going in. you mention how close they are the most forward position is