U.S. President-elect Joe Biden’s pick to lead the State Department has said the U.S. is still a "long way” from securing a long-term deal with Tehran that improves the original Iran nuclear agreement, but insisted that the country’s ability to develop weapons of mass destruction be put "back in the box.”

Secretary of state nominee Antony Blinken reiterated the incoming administration’s desire to re-enter the 2015 accord that President Donald Trump withdrew from three years ago. But Blinken — who said the accord helped restrain Iran’s nuclear program — added that Tehran must return to compliance with the terms of the deal first, and he vowed to work closely with Congress as potential talks progress.

"If Iran comes back into compliance we would, too, but we would use that as a platform with our allies and partners who would once again be on the same side with us, to seek a longer and stronger agreement,” Blinken said in testimony Tuesday to the Senate Foreign Relations Committee. "Having said that, I think we’re a long way from there. We would have to see once the president-elect is in office what steps Iran actually takes and is prepared to take.”