>> sandra: a senior u.s. defense official says the movement towards the capital is stalled, the official also says 80% of russian forces prestaged for the invasion have now entered ukraine. national security correspondent jennifer griffin is at the pentagon with the latest from there for us. >> i've just come out of a briefing with a senior u.s. defense official tells us there is no discussion right now of setting up a no fly zone and as you mentioned, more than 80% of russian prestage combat power is now deployed inside ukraine. some russian units have been captured, they have evidence that some russian soldiers have surrendered even without a fight. we are told of the -- that the main advance on the capital that long convoy that we have seen images of, there is no