The video call between Presidents Joe Biden and Vladimir Putin lasted about two hours. It will take months to figure out if the two sides managed to defuse the crisis over Ukraine.

Biden sought to send a clear message: Russia must not go ahead with an invasion of Ukraine as the U.S. fears it might, and would face massive economic sanctions if it does. Putin, meanwhile, wanted the U.S. to know that Russia won’t tolerate NATO expanding farther east or deploying weapons in Ukraine.

Biden didn’t accede to Putin’s "red line” demands. And Putin made no promise to withdraw the 175,000 troops he’s amassing along the Ukrainian border. That highlighted how U.S. officials appeared to have no new clarity on the fundamental question at the heart of this most recent standoff with Russia — whether Putin intends to invade Ukraine a second time, after taking Crimea in 2014.