WASHINGTON — If the US Congress shoots down the Iranian nuclear deal, America will eventually be pressured into a military strike against Tehran’s nuclear facilities, which will in turn increase terror against Israel, US President Barack Obama told Jewish leaders Tuesday, a source who was present at the meeting said.

During the two-hour meeting, Obama said it was legitimate for opponents of the deal to lobby lawmakers to reject it, but added that a discussion focused on personal attacks, rather than the merits of the deal, could jeopardize the coherence of the American Jewish community and ultimately the resilience of US-Israel relations, according to Greg Rosenbaum, the chair of the National Jewish Democratic Council.

In a bid to convince the US Jewish community to support the deal, Obama and Vice President Joe Biden hosted 20 Jewish leaders from across the political and religious spectrum at the White House’s Cabinet Room, hours after Prime Minister Benjamin Netanyahu urged members of the Jewish Federations of North America in a video address to fight the deal.

Speaking to the Israel Diplomatic Correspondents Association after the meeting with the president, Rosenbaum said that Obama had meticulously tried to debunk the arguments against the Iran deal, while acknowledging that the agreement was “by no means perfect.”

Some of the opponents of the deal have complained that the administration has been portraying them as warmongers, by asserting that the only alternative to the deal — signed last month in Vienna between Iran and six world powers — is war, according to several officials who attended the meeting. Obama replied that he truly believes that if the deal will be rejected by Congress, the ultimate result will be a military strike, Rosenbaum said.

If Congress succeeds in killing the deal and Iran were to subsequently walk away from the agreement and start enriching uranium again to weapons-grade levels, the opponents of the deal will pressure the US government into launching a preemptive strike against the Islamic Republic’s nuclear facilities, the president was said to have argued.

“But the result of such a strike won’t be war with Iran,” Rosenbaum said, quoting the president.

Iran is not going to launch a full-fledged assault on America, knowing that its military, with an annual budget of $15 billion, stands no chance against the US Army and its budget of close to $600 billion, the president said. Rather, Iran’s terrorist proxies will attack American and Israeli targets, for instance by ramming aircraft carriers or arming terrorist groups along Israel’s borders.

Hezbollah members mourn during the funeral of a comrade who was killed in combat alongside Syrian government forces in the Qalamun region, on May 26, 2015, in the southern Lebanese village of Ghaziyeh. (AFP PHOTO / MAHMOUD ZAYYAT)

Hezbollah members mourn during the funeral of a comrade who was killed in combat alongside Syrian government forces in the Qalamoun region in the southern Lebanese village of Ghaziyeh, May 26, 2015. (AFP/Mahmoud Zayyat)

“They will fight this asymmetrically. That means more support for terrorism, more Hezbollah rockets falling on Tel Aviv,” Rosenbaum quoted Obama as saying. “I can assure that Israel will bear the brunt of the asymmetrical response that Iran will have to a military strike on its nuclear facilities.”

During the White House briefing, Obama indicated that he was ready and willing to meet Netanyahu and discuss, “in more than general terms,” upgrading Washington’s military assistance to Israel, but that the Israeli leader has been unwilling to do so at this point, Rosenbaum said.

The president also implied that he had offered a meeting with Netanyahu – similar to his meeting with leaders of the Arab Gulf states – but that the prime minister had rebuffed the overture, according to Rosenbaum. The president believes that Netanyahu refuses to hold discussions about financial compensation because he intends to fight the deal, he said.

During the White House briefing, which was characterized by participants as “serious” and “contentious,” opponents and advocates of the deal clashed verbally, each side accusing the other of badmouthing it. Opponents said the administration portrayed them as seeking war with Iran, while those in favor of the deal said they had been accused of being kapos and helping to prepare for a second Holocaust.

Obama said he was under no illusion that he could convince all Jewish leaders to agree with him on the Iran issue, and that opponents have a legitimate right to spend as much money as they wish in lobbying against the agreement. If, however, the debate is not held on the merits of the deal but with name-calling, invective, and misleading and false facts, “I fear you are going to weaken the coherence of the Jewish community and ultimately the strength of the US-Israel relationship,” Obama said, according to Rosenbaum.

President Barack Obama and AIPAC President Lee Rosenberg wave to the crowd gathered at the AIPAC convention in Washington in May 2011. (photo credit: AP/Jose Luis Magana)

President Barack Obama and AIPAC President Lee Rosenberg wave to the crowd at the AIPAC convention in Washington in May 2011. (AP/Jose Luis Magana)

In a prolonged back-and-forth with Lee Rosenberg, chairman of the American Israel Public Affairs Committee, Obama reportedly said it was fine for the organization to spend millions of dollars on efforts to kill the deal. But, he added, AIPAC’s newspaper ads should not say that Jews who support the deal are bad Jews or hurting Israel’s security. The heated debate over the deal’s risks is tearing the Jewish community apart and causing “irreparable” damage, he said.

Indeed, the president told AIPAC that the newspaper ads and fact sheets it has been handing out are “inaccurate” and that he has to spend nearly an hour with every legislator that AIPAC approached to set the record straight, according to Rosenbaum.

During his video address earlier Tuesday to American Jews, Netanyahu warned that, if ratified, the nuclear deal would lead to war and a “nightmare” regional nuclear arms race.

“This deal will bring war,” he cautioned. “Iran can keep the deal or Iran can cheat on the deal,” Either way, it will have the bomb, Netanyahu said, before adding, “hundreds of bombs.” Furthermore, he said, addressing the audience, Iran has been building intercontinental ballistic missiles in order “to hit you,” not Israel.

The American Jewish community is seen as a key barometer for the fate of the deal, as Congress enjoys a 60-day review period of the agreement ahead of a crucial vote on a resolution of disapproval or approval in September. A number of Jewish organizations have called on members to lobby their representatives to oppose the agreement, which critics say won’t prevent Tehran from becoming a nuclear power and enables it to bolster its support for extremist regional elements.

Other organizations, like the American Jewish Committee, say that they are still reviewing the details of the agreement, and have yet to determine an official stance on it. J Street has been at the vanguard of advocacy efforts for the deal, quickly announcing its support for the agreement and arguing that it presents the best opportunity for reining in Iran’s centrifuges.

Rebbeca Shimoni Stoil and Elie Leshem contributed to this report.