The American Israel Public Affairs Committee (AIPAC) is opposed to Prime Minister Benjamin Netanyahu’s upcoming speech to Congress on the Iranian nuclear threat and urged the Israeli leader to reconsider in anticipation of the strain it would place on US-Israel ties, an Al-Monitor report on Thursday maintained.

According to a report by columnist Ben Caspit, one of the heads of the pro-Israel lobby said the group was “in shock” after Netanyahu announced he would address Congress, calling it “AIPAC’s Day of Atonement,” and “the lowest point we have ever reached.” After Netanyahu accepted the invitation by House Speaker John Boehner, bypassing the White House, AIPAC laid out the negative ramifications the move would have on diplomatic ties.

“AIPAC prepared a detailed presentation that was given to Netanyahu with all the negative repercussions they believe would result from the controversial invitation to Congress and the cumulative damage,” Caspit wrote.

“On February 25 behind closed doors, one of the heads of AIPAC said, to paraphrase: All the things we warned him of, are materializing. We foresaw the domino effect that took place, the boycott by more and more Democratic Congress members, the significant deterioration in relations with Democratic legislators, the talks about boycotting the AIPAC convention (that is also being held at the beginning of March) by the administration. We protested, we warned. And who wasn’t impressed? Netanyahu. He’s coming,” he wrote.

The upcoming speech, which is openly opposed by the White House, some Democratic legislators and many within the US Jewish community, angered the Obama administration and US lawmakers, who charged that the invitation to address Congress disregarded diplomatic protocol and was an attempt by Netanyahu to derail the US-brokered nuclear negotiations with Iran, Obama’s signature foreign policy objective.

Netanyahu’s speech is controversial because it puts Israel on a collision course with the Obama administration as it negotiates with Iran over its nuclear program — talks that in their current form could lead to a deal that potentially poses an existential risk to Israel, Netanyahu has warned. Thus, he intends to argue before Congress on March 3 that the international community should increase its pressure on Iran, rather than ease sanctions against it under the reported terms of the emerging nuclear deal.

The speech is also set just two weeks before the prime minister faces elections back home, and critics in Israel and the US have accused Netanyahu of using the address to drum up support for his Likud party.

The AIPAC leadership was split on how to respond to Netanyahu’s decision to go ahead with the speech, the report said.

“Some thought that they should directly implore Netanyahu to cancel his speech to Congress, to suggest alternatives to him. Such a move, however, would have run counter to AIPAC’s very DNA, since AIPAC is Netanyahu’s lobby and not the reverse. On the other hand, almost all the organization’s higher-ups were aware and convinced of the immensity of the damage that Netanyahu’s actions would bring to Israeli-American relations in the medium- and long-terms. It was hard for them to keep silent,” it said.

Caspit wrote that Netanyahu will likely present “new information, evidently intelligence based” on the Iranian nuclear program during his address.

The address has been criticized by US National Security Adviser Susan Rice, who said in an interview this week that the manner in which Netanyahu’s speech was arranged — and his insistence on going ahead with it — had become a partisan issue that was “destructive of the fabric of the relationship” between Israel and the US.

Secretary of State John Kerry on Wednesday called Netanyahu’s judgment into question, pointing to the Israeli premier’s support for the US Iraq war (Netanyahu was a private citizen at the time, and Kerry had in the past backed the war). The address has also drawn criticism at home, and from US Jewish groups, including the Anti-Defamation League.

Despite the tensions, AIPAC announced Thursday that the Obama administration has confirmed that Rice and UN envoy Samantha Power will address its annual policy conference, beginning Sunday.

Despite what has been characterized by some as a growing partisan divide on issues related to Israel, AIPAC will host prominent members of both parties’ congressional delegations during its three-day conference. House Majority Leader Kevin McCarthy (R- CA), Democratic House Whip Steny Hoyer (D-MD), Senate Majority Leader Mitch McConnell (R-KY), Senator Robert Menendez (D-NJ) and Senator Lindsey Graham (R-SC) will all address the plenary sessions of the annual meeting.

AIPAC officials said Thursday that although the finalized schedule has not been published, they expect that more than half the Senate and two-thirds of the House of Representatives will be in attendance over the course of the conference.

Organizers said that this year’s policy conference is sold-out in attendance for the first time ever. The more than 16,000 participants make 2015 the largest conference in AIPAC’s history.

Meanwhile, Netanyahu turned down an invitation to meet privately with Senate Democrats next week during his visit to Washington, saying the session “could compound the misperception of partisanship” surrounding his trip. He later accepted an invitation to hold a meeting with a bipartisan Congressional delegation while in Washington, a senior official in the Prime Minister’s Office said Thursday.