would have no borders, why would we need those sanctions then? >> reporter: as vladimir putin watches nuclear drills, u.s. officials fear attacks are iminant. >> if you look at the staps he's in today it's apparent he has made a decision and they're moving into the right positions to be able to conduct an attack. i'm pamela brown in washington. you're in the "cnn newsroom." great to have you along with us on this saturday evening. and we begin this hour with the russia, ukraine crisis and a new measure of the growing concern. president biden will convene a national security council meeting tomorrow in the situation room to discuss the troubling developments and escalating violence. >> go faster.