"Americans had better realize that totalitarianism and pressures will not work in nuclear talks with Iran because Tehran will not compromise an iota of its inalienable nuclear rights," Aboutorabifard said in the city of Birjand, Northeastern Iran, on Thursday night.

He reiterated the US should end its excessive demands in the ongoing talks with Tehran within the framework of the Group 5+1.

In relevant remarks on Sunday, Iranian Foreign Minister Mohammad Javad Zarif who held a meeting with his US counterpart John Kerry in Geneva on Saturday said that differences over the contents of a final nuclear deal are still in place.

"There are still numerous differences, and efforts will be made in various meetings so that these differences will be reduced to minimum levels and they will be studied in the next ministerial meeting," Zarif told the state-run TV.

He said the "differences are mainly those that have been discussed publicly".