Russia's troop buildup near Ukraine raises tensions in region ahead of Biden and Putin video call

President Biden’s video call with Russia’s Vladimir Putin on Tuesday comes amid tensions over Russia's troop buildup near Ukraine. The buildup is raising alarms because Russia invaded and annexed territory in the eastern part of Ukraine in 2014. Senior foreign correspondent Charlie D'Agata reports. Each weekday morning, "CBS Mornings” co-hosts Gayle King, Tony Dokoupil and Nate Burleson bring you the latest breaking news, smart conversation and in-depth feature reporting. "CBS Mornings" airs weekdays at 7 a.m. on CBS and 8 a.m. ET on CBSN. Subscribe to “CBS Mornings” on YouTube:    / cbsmornings   Watch CBSN live: http://cbsn.ws/1PlLpZ7c​ Download the CBS News app: http://cbsn.ws/1Xb1WC8​ Follow "CBS Mornings" on Instagram: https://bit.ly/3A13OqA Like "CBS Mornings" on Facebook: https://bit.ly/3tpOx00 Follow "CBS Mornings" on Twitter: https://bit.ly/38QQp8B Subscribe to our newsletter: http://cbsn.ws/1RqHw7T​ Try Paramount+ free: https://bit.ly/2OiW1kZ For video licensing inquiries, contact: [email protected]