A U.S. diplomatic spokesperson remarked that “there has been some progress [in JCPOA talks] relative to the beginning of December in identifying the hard issues left to be negotiated”, adding: “the fundamental situation really remains. Iran needs to exercise restraint in its nuclear program and pursue negotiations in Vienna seriously… otherwise, the benefits that the JCPOA conveyed in terms of nonproliferation will continue to be diminished, and there will be no realistic way back to the deal”.