President Joe Biden has criticized Russian President Vladimir Putin's decision to suspend the last remaining U.S.-Russia nuclear arms control treaty, the New START treaty, which was signed in 2010. Putin announced the suspension of the treaty during his state of the nation address, raising tensions between the two countries. Biden, currently in Warsaw, Poland, called the decision a "big mistake" and Putin said Russia should be prepared to resume nuclear weapons tests if the U.S. did so first.