By Matt Spetalnick and Allyn Fisher-Ilan
WASHINGTON/JERUSALEM (Reuters) - Israeli Prime Minister Benjamin Netanyahu on Sunday pressed world powers to take a hard line with Iran in negotiations for a final nuclear deal, urging them to demand that Tehran abandon all uranium enrichment, halt its ballistic missile program and end a "genocidal" anti-Israel policy.
One day after President Barack Obama deemed it unrealistic to believe Iran could be compelled to dismantle its entire nuclear infrastructure, Netanyahu said Tehran should have to take apart all centrifuges used to refine uranium, despite its insistence it would never agree to do so.
Netanyahu, deeply skeptical over an interim six-month deal reached with Iran in Geneva in late November, also suggested that the imposition of new sanctions could help the West secure a "better deal" in the next round of negotiations. Obama has urged Congress against further punitive measures for now.
While delivering a pointed rebuttal to some of Obama's arguments on Iran, Netanyahu took pains to avoid any new diplomatic clash with the U.S. president. He instead played down their differences and lauded the recently strained U.S.-Israeli bond as the "indispensable alliance."
But with the hawkish Israeli prime minister urging the international community to "beware" of Iran's intentions, he made clear that Israel and the United States are hardly on the same page.
"The world must not allow Iran to be a threshold nuclear weapons state, with the option to cross that threshold at a time of its choosing," Netanyahu told a foreign policy forum in Washington, speaking via satellite link from Jerusalem.
While the United States wants talks limited to Iran's nuclear program, Netanyahu urged a broader approach, calling on world powers to demand suspension of Iranian missile development - which Israel sees as a security threat - and an end to Tehran's weapons supplies to anti-Israel militants.
Addressing the same forum on Saturday, Obama defended diplomacy with Iran but sought to reassure Israelis with a pledge to step up sanctions or prepare for a potential military strike if Tehran fails to abide by the pact.
He argued, however, it was unreasonable to envision a deal in which "we'll destroy every element and facility" and argued instead that world powers could accept a "modest" Iranian civil nuclear program subject to intensive international monitoring.
But Netanyahu made clear that Israel considers any Iranian enrichment capacity to have military potential - despite Tehran's denial that it seeks a nuclear bomb.
In his speech, Netanyahu spoke only briefly of the need to "take apart all the centrifuges" that Iran operates. But later, in a joint appearance with the visiting Dutch prime minister near Tel Aviv, he stressed the point.
"I called today for the dismantling of all centrifuges," he told reporters. "All centrifuges means that there's no enrichment ... and therefore we think that that should be part and parcel of a deal."
Netanyahu stopped short of repeating his denunciation of the Geneva deal as a "historic mistake," widely interpreted as a swipe at Obama, with whom he has had testy relations.
Instead, Netanyahu appears to have set his sights on trying to ensure that world powers squeeze maximum concessions from Iran as they try to craft a comprehensive settlement.
Adding a new twist to his pressure campaign, Netanyahu told a largely pro-Israel audience in Washington that Iran was "committed to our destruction" and that any final deal must "include a demand to change its genocidal policy."
He accused Iran of supplying rockets to anti-Israel Islamist groups Hezbollah, Hamas and Islamic Jihad and also cited a recent comment by Iranian Supreme Leader Ayatollah Ali Khamenei calling Israel the "rabid dog" of the Middle East.
Iran's new president, Hassan Rouhani, a relative moderate, has steered clear of the Holocaust-denial rhetoric of his predecessor, Mahmoud Ahmadinejad, in reaching out to the West. Rouhani has also pledged Iran will never seek a nuclear bomb.
Relations between Israel and the United States, traditionally the closest of allies, have been strained by the preliminary agreement, which was designed to halt advances in Iran's nuclear program and buy time for further negotiations.
Speaking at the Brookings Institution's Saban Forum, Netanyahu said a diplomatic solution is preferable but that a credible military threat and tough sanctions are vital to make that possible. And he called for steps to prevent further erosion of existing sanctions.
There is concern within the Obama administration that Netanyahu's criticism of the Geneva deal could add impetus to calls by pro-Israel U.S. lawmakers for new sanctions.
U.S. officials have appealed to Congress not to push for new punitive measures during negotiations, saying it could alienate Iran and other countries involved in the talks.
Israel's opposition to the deal has raised speculation that it might carry out long-threatened strikes against Iran. Netanyahu reiterated his vow that Israel must have the ability to "defend itself by itself," but he issued no direct threats.
While Israel is widely assumed to have the region's only nuclear arsenal, many independent analysts believe it lacks the conventional clout to cause lasting damage to Iran's nuclear facilities. The Israelis are also unlikely to go it alone as their most important foreign partner is engaged in diplomacy.
Turning to the Israeli-Palestinian dispute, Netanyahu said a nuclear-armed Iran would be the greatest threat to a potential Middle East peace accord.
He did not echo the hopeful outlook for U.S.-brokered talks that Obama - who has made the issue a top foreign policy priority - painted a day earlier - and said that any agreement that might emerge would initially result in a "cold peace."
While putting the onus on the Palestinians, Netanyahu reiterated he was ready for "historic compromise" but offered nothing new. Palestinians say the negotiations have been hampered by Israeli settlement building on occupied West Bank land they want for a state.
(Reporting by Matt Spetalnick; Editing by Christopher Wilson and Paul Simao)