President Joe Biden plans to talk by phone with Russian President Vladimir Putin on Thursday as the U.S. and its allies raise alarm about Russia’s troop buildup on the Ukraine border. The leaders will “discuss a range of topics, including upcoming diplomatic engagements with Russia,” National Security Council spokeswoman Emily Horne said in a statement. The talks follow a Dec. 7 Biden-Putin telephone exchange in which the American president affirmed a commitment to Ukraine’s sovereignty and territorial integrity and warned that Russian aggression would be met with unprecedented economic penalties. The U.S. has told European allies that the massive Russian military presence near Ukraine might be preparation for an invasion as early as next month. The U.S. remains gravely concerned about the buildup, a senior Biden administration official said Wednesday, and is prepared to provide Ukraine with additional assistance should Russia invade. Subscribe to our YouTube channel: https://bit.ly/2TwO8Gm​ Bloomberg Quicktake brings you live global news and original shows spanning business, technology, politics and culture. Make sense of the stories changing your business and your world. To watch complete coverage on Bloomberg Quicktake 24/7, visit http://www.bloomberg.com/qt/live​, or watch on Apple TV, Roku, Samsung Smart TV, Fire TV and Android TV on the Bloomberg app. Connect with us on… YouTube: https://www.youtube.com/user/Bloomberg​ Breaking News on YouTube: https://www.youtube.com/c/BloombergQu...​ Twitter: https://twitter.com/quicktake​ Facebook: https://www.facebook.com/quicktake​ Instagram: https://www.instagram.com/quicktake