U.S. Secretary of State John Kerry has said there had been some progress in talks with Iran on its nuclear program, but warned there was "a long way to go" to reach a deal.
Speaking on the sidelines of the UN Human Rights Council in Geneva on March 2, Kerry said, "the clock is ticking."
He made the comments before he and Iranian Foreign Minister Mohammad Javad Zarif met for another round of talks on Tehran's nuclear program later in the day in Montreux, Switzerland.
The United States, Russia, China, Britain, France, and Germany are seeking an agreement with Tehran that would rein in Iran's nuclear program in exchange for relief from economic sanctions.
Tehran dismisses Western suspicions it is using its civilian nuclear program to also secretly develop nuclear weapons.
After missing two self-imposed deadlines last year, negotiators are seeking a political framework by the end of March and a full deal by June 30.
Kerry warned that public discussion of select details of the ongoing negotiations will make it more difficult to reach an agreement with Iran.
He did not elaborate, but Israeli Prime Minister Benjamin Netanyahu will speak in opposition to a potential Iran deal in an address to Congress on March 3.
Israeli officials say Netanyahu plans to discuss elements of the negotiations that he finds problematic and dangerous to his country.
Zarif told reporters in Geneva that a deal could be concluded this week if the negotiating sides have sufficient political will and agree to remove sanctions on Tehran.
"If they want an agreement, sanctions must go," he said. “Sanctions, they have to realize, are not an asset, have never been an asset, they are liability and this liability, the sooner they remove this liability from the table, the sooner we will get to an agreement."
He said Iran had demonstrated its political will by bringing its highest authorities to the negotiation table and leaving "no stone unturned."
On March 2 in Vienna, the head of the United Nations' nuclear watchdog, the International Atomic Energy Agency, said Iran had still not handed over key information to his staff.
Yukiya Amano told the IAEA’s board of governors that the agency could not “conclude that all nuclear material in Iran is in peaceful activities."
Amano said the IAEA remains ready to accelerate the resolution of all outstanding issues, adding that "this process cannot continue indefinitely."