Israeli Prime Minister Benjamin Netanyahu warned the U.N. General Assembly on Tuesday not to fall prey to Iranian President Rouhani’s smooth talk.

Netanyahu argued that since the 1979 revolution, Iran has used different rhetorical strategies, but the regime has not changed; it is as determined as ever to build nuclear weapons. Rouhani is not moderate, Netanyahu said, and the international community should not be fooled.

Providing historical context, Netanyahu noted that Iran’s Supreme National Security Council under Rouhani’s leadership from 1989 to 2003 ordered the assassination of opposition leaders, the bombing of the Jewish community center in Buenos Aires, and the bombing of the Khobar Towers in Saudi Arabia, which killed 19 Americans. Not only did Rouhani play a major role in Iran’s terrorist campaign, but as Iran’s chief nuclear negotiator from 2003 to 2005, he also orchestrated the deception strategy that allowed Iran to “advance its nuclear weapons program behind a smoke screen of diplomatic engagement and very soothing rhetoric.”

Netanyahu warned that Rouhani is “a wolf in sheep’s clothing.” “He fooled the world once. Now he thinks he can fool it again.”

Netanyahu urged the U.N. to maintain sanctions on Iran, which have crippled its economy. “That’s why he launched his charm offensive.” He pointed out that Iran has no intention of giving up its nuclear ambitions. Only more economic pressure, coupled with a credible military threat, will finally force Iran to dismantle its nuclear program.

Netanyahu warned against agreeing to a “partial deal” with Iran that would “lift sanctions that have taken years to put in place in exchange for cosmetic concessions that will take only weeks for Iran to reverse.”

The international community should not forget the lessons of the 20th century, Netanyahu warned: “The last century has taught us that when a radical regime with global ambitions gets awesome power, sooner or later its appetite for aggression knows no bounds.” Only by maintaining relentless pressure on Iran to dismantle its nuclear program—and remaining firm despite Rouhani’s softening speech—can the danger of a nuclear-armed Iranian regime be averted.