"Today sanctions are stronger than ever. They've forced the Iranians to take note, to sit down and to talk," Barak said to a group of journalists at the Foreign Press Association in Jerusalem, according to AFP.
"The P5+1 engagement with Iran, however, does not fill me with confidence,” he said. “I may sound pessimistic, but the state of Israel cannot afford to be duped."
Barak’s criticism of the nuclear negotiations — which began last month in Istanbul and will resume later this month in Baghdad — follow that of Israeli Prime Minister Benjamin Netanyahu, who said Iran was getting a “freebie” with the nuclear talks.
President Obama took issue with Netanyahu’s comments, saying at a press conference that “the notion that somehow we've given something away, or ‘a freebie,’ would indicate that Iran has gotten something.”
Talk of an Israeli attack on Iran this year to stop its nuclear program has dissipated in recent weeks as Iran agreed to return to the negotiating table and Obama urged Israel not to strike.
Even some Israeli officials have softened their line on Iran, as Israel Defense Forces Chief of Staff Benny Getz said last week that “the Iranian leadership is composed of very rational people" and had not yet decided whether it would build a nuclear weapon.
Barak had warned earlier this year that Iran was close to entering a “zone of immunity” where Israel would not be able to stop Tehran from proceeding with development of a nuclear weapon.
The United States, Israel and their allies suspect Iran is seeking a nuclear weapon, while Iran insists its nuclear program is for peaceful purposes only.
Barak on Monday said that Iran was “getting closer” to the zone of immunity.
“Actions speak louder than words. On the ground, the Iranians keep moving and are determined to obtain nuclear weapons,” Barak said, according to AFP.