"For years we stood alone against these twin threats and I think that the situation has changed for the better," Netanyahu said.
Netanyahu unsuccessfully tried to block the landmark deal that which gave Iran relief from crippling sanctions in exchange for curbs on its nuclear program when it was negotiated in 2015 under President Barack Obama. The Israeli leader has found a welcome ally in President Donald Trump, who last month withdrew the United States from the deal.
Both the U.S. and Israel hope Trump's withdrawal can lead all sides into addressing what they say are the deal's shortcomings — including "sunset" provisions that end restrictions on Iranian nuclear activities, such as enriching uranium, as well as permitting Iran to continue to develop long-range missiles.
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Netanyahu says that as the deal expires over the next decade or so, Iran will emerge with the ability to produce a nuclear bomb in a very short time.
In addition to the U.S., the nuclear deal was negotiated by Germany, France, Britain, Russia and China. The remaining members have said they remain committed to the deal. Iran for now also is honoring the agreement, though some top officials have suggested it resume its enrichment activities.
French President Emmanuel Macron's office said France will insist on having a dialogue with Iran.
An official in his office said Macron, along with Germany and the U.K., have all been "clear" that they will work with the existing deal, viewing it as the best way to control Iran's nuclear activity. The official spoke on condition of anonymity under customary briefing guidelines.
Oded Eran, a former Israeli ambassador to the European Union, said Netanyahu is unlikely to change the minds of his counterparts on the necessity for the current agreement.
But he said he may sway them on certain details not included in the deal, such as Iran's missile development and the expiration of restrictions on nuclear activity.
"There's no secret that the prime minister wants to completely change the agreement and replace it with an agreement that covers the issues that are missing," said Eran, senior researcher at the Institute for National Security Studies at Tel Aviv University. "I don't think that he will change the policy, but he will get maybe a commitment to work on the missing points."
While Iran says its nuclear program is for peaceful purposes only, Israel recently released tens of thousands of seized Iranian nuclear documents that Netanyahu said prove Iran pursued a nuclear bomb in the past. He is likely to discuss this information with the other leaders.
Eran said Netanyahu may make more progress on his other demand — expelling Iranian forces from Syria.
Netanyahu has long identified Iran as Israel's greatest threat, pointing to its nuclear program, calls for Israel's destruction and support of anti-Israel militant groups.
Israel fears that as the Syrian civil war winds down, Iran, whose forces and Shiite proxies have backed President Bashar al-Assad, will turn its focus to Israel.
The Israeli air force is believed to have carried out a number of airstrikes on Iranian positions in Syria. Last month, the bitter enemies openly clashed when Iran fired dozens of rockets at Israeli positions in the Golan Heights, and Israel responded by striking several Iranian targets in Syria.
Eran said he believes the European leaders are receptive to Israeli concerns.
"I think he will reach an understanding on the question of Iran's deployment in Syria and other activities of Iran in the region," he said.