US issues veiled threat over Iran's nuclear program

Ahead of the US-Iran nuclear talks in Vienna, the American envoy said Washington will not “sit idly” if Tehran chooses to stall the talks and advance its atomic program to the point it’s “too close” to a working weapon.“We’re prepared to get back into the deal and to lift all of the sanctions that are inconsistent with the deal. So if Iran wants to get back into the deal, it has a way to do that,” the State Department’s special envoy for Iran