MOSCOW - Presidents Joe Biden and Vladimir Putin will speak in a video call Tuesday, the Kremlin said, as tensions between the United States and Russia escalate over a Russian troop buildup on the Ukrainian border that's seen as a sign of a potential invasion.Kremlin spokesman Dmitry Peskov confirmed plans for the conversation to Russia's state news agency RIA Novosti and said it will take place Tuesday evening. "The presidents will decide themselves" how long their talk will last, he said Saturday.The White House did not immediately comment on the announcement.RELATED: Biden-Putin summit: Leaders set 'consultations' on updating nuclear pactThe last known call between the leaders was in July, when Biden pressed Putin to rein in Russia-based.