saudi arabia. a new offensive to drive out iranian-backed rebels who seized control of the capital and key military sites. officials say the saudi campaign was quickly planned, catching top u.s. military commanders off guard. >> general, when were you told by the saudis that they were going to take military action in yemen? >> sir, i had a conversation with achad right before they took action. so shortly before. >> right before they took action. >> yes, sir. >> that's very interesting. >> reporter: the white house has already committed significant assistance. the u.s. military is helping the saudis plan bombing missions over yemen, providing targeting intelligence from satellites overhead and making awac surveillance planes and aerial refueling aircraft available as well. the general says he doesn't know if it will all work. >> i don't currently know the