In this handout image provided by the Israeli Government Press Office (GPO), Israeli Prime Minister Benyamin Netanyahu (L) meets with Democratic delegates from the U.S. House of Representatives headed by Minority Whip Rep. Steny Hoyer (D-Md.) August 6, 2013 in Jerusalem. The delegation is meeting with both Israeli and Palestinian government officials. (Moshe Milner/GPO/Getty Images)

Saying the United States and the world are being misled by a false face into thinking that Iran has a more moderate leader, Israeli Prime Minister Benjamin Netanyahu on Wednesday charged that Iran is not only continuing its nuclear program but has accelerated its quest to build a bomb in the weeks since voters there elected Hassan Rouhani president.

Calling Rouhani “a wolf in sheep’s clothing,” Netanyahu told U.S. lawmakers at a meeting here that he is aware that some have placed their hopes in the new Iranian president. But the Israeli leader warned: “He knows how to exploit this, and yesterday he called for more talks. Of course he wants more talks. He wants to talk and talk and talk. And while everybody is busy talking to him, he’ll be busy enriching uranium. The centrifuges will keep on spinning.”

In his first news conference since taking office, Rouhani said Tuesday that he is willing to participate in nuclear negotiations with the international community but stopped short of saying he would engage in direct talks with the United States.

Israel’s leadership has declared Iran’s uranium-enrichment program an “existential threat,” and Netanyahu has sought assurances from the Obama administration that it would confront Iran, militarily if necessary.

“Iran’s work and quest towards the achievement of atomic weapons not only continues, it continues unabated — it’s actually accelerated,” Netanyahu said.

Also troubling, he said, were recent reports that Iran may be operating a heavy-water factory to produce plutonium, which can be used in a nuclear weapon. “So the situation, unhappily, is not getting any better, it’s actually getting worse,” Netanyahu said.

Rouhani, a former chief nuclear negotiator for Tehran, is known in some circles as “the diplomatic sheik.” That has Israel’s political and defense leadership worried that the United States and Europe might be tempted to relax, rather than ratchet up, pressure on Tehran to curb its nuclear ambitions.

“Rouhani is charming, he is cunning, and he will smile all the way to the bomb,” Yuval Steinitz, Israel’s minister for international affairs, strategy and intelligence, said in an interview.

Steinitz said that rather than negotiate with Tehran, the United States and the international community should tighten the economic sanctions against Iran’s already stagnating economy.

In his remarks to journalists Tuesday, Rouhani said, “If we feel that the Americans are truly serious about resolving problems, Iran is serious in its will to resolve problems and dismiss worries.”

But he said Iran would not be bullied, and during his news conference, the cleric repeatedly referred to unspecified “warmongering pressure groups” working for an unidentified country, which most listeners presumed to be Israel.

The Israeli intelligence minister said Tehran should hear from the United States and the international community that it has only two choices — voluntarily shutter its uranium enrichment program or “see it destroyed with brute force,” which he envisioned as “a few hours of airstrikes, no more.”

Steinitz shrugged at the possible consequences and said he could envision Iran firing “several hundred missiles” at Israel in retaliation, producing “very limited damage because we can intercept many of them.”