Vladimir Putin said Russia may consider formally adding the possibility of a preventive nuclear first strike to disarm an opponent to its military doctrine, just days after warning that the risk of atomic war is rising. He spoke in Kyrgyzstan. Bloomberg's Annmarie Hordern reports on "Balance of Power." Follow Bloomberg for business news & analysis, up-to-the-minute market data, features, profiles and more: http://www.bloomberg.com Connect with us on... Twitter: https://twitter.com/business Facebook: https://www.facebook.com/bloombergbusiness/ Instagram: https://www.instagram.com/quicktake/?hl=en