US demands concessions at nuke talks, Iran pushes back ahead of July 20 deal target date

Iran is pushing back against U.S. demands for concessions as negotiators haggle over what curbs Tehran must accept on its nuclear program to win an end to the sanctions choking its economy.

Both Iran and the six world powers it is talking with hope to seal a deal by July 20. But they parted last month without significant progress — and came to the table Wednesday demanding that the other side blink first.

Iranian Foreign Minister Mohammad Javad Zarif said "we have never bowed down to imposition, and we will not accept it in this round of talks either."

U.S. State Department spokeswoman Marie Harf urged Tehran to "make the choices that we think that they have to make" while British Foreign Secretary William Hague spoke of "significant differences."