Republican presidential hopeful Donald Trump addresses the 2016 American Israel Public Affairs Committee (AIPAC) policy conference in Washington, D.C., March 21, 2016. Brendan Smialowski/Getty Images

Republican front-runner Donald Trump addressed the annual policy conference of the American Israel Public Affairs Committee, or AIPAC, Monday evening in Washington, D.C., in a speech that touted his great relationship with Israel, bashed the Iran nuclear deal and clarified his position on the Israeli- Palestinian conflict.

“My No. 1 priority is to dismantle the disastrous deal with Iran,” Trump said, drawing applause. "This deal is catastrophic for America, for Israel, for the whole of the Middle East."

Trump said that if he becomes president, he will adopt a strategy that focuses on standing up to Iran's aggressive push to destabilize and dominate the region and on totally dismantling Iran's global terror network .

The real estate tycoon bashed President Barack Obama, saying that he "may be the worst thing ever to happen to Israel" said that he has treated Israel "very, very badly." Trump also took the opportunity to take a swing at rival candidate Hillary Clinton, calling her a "total disaster."

During his speech, Trump emphasized that a resolution imposed by the United Nations on the Israeli-Palestinian conflict would only delegitimize Israel further and would reward Palestinian terrorism. He said that in order for a solution to hold, the parties need to negotiate it themselves.

“The United States can be useful as a facilitator of negotiations, but no one should be telling Israel it must abide by some agreement made by others thousands of miles away that don’t even really know what’s happening to Israel, to anything in the area, it’s so preposterous — we’re not gonna let that happen,” Trump said. “I will veto any attempt by the U.N. to impose its will on the Jewish state. It will be vetoed, 100 percent.”

Trump seemed to fare well with the crowd at AIPAC; he received eruptions of cheers and applause as well as numerous standing ovations.

He made sure to mention his daughter, who converted to Judaism when she married and is pregnant. “My daughter Ivanka is about to have a beautiful, Jewish baby,” Trump said, wrapping up his speech.

In the past, the billionaire businessman has made contradicting statements regarding Israel, prompting people to question his foreign-policy expertise. During a debate in Florida earlier this month, Trump said that there was “no one more pro-Israel” than him. However at a forum in February, he had said he would like to remain neutral between the two parties involved with the Israeli-Palestinian conflict.

"I'm a negotiator. If I go in, I'll say I'm pro-Israel, and I've told that to everybody and anybody that would listen,” Trump said during a debate earlier this month, NPR reported. “But I would like to at least have the other side think I'm somewhat neutral as to them so that we can maybe get a deal done."

Foreign policy observers were expected to pay close attention to Trump’s speech at AIPAC to see whether he would abandon his flip-flopping rhetoric.

"This speech is an important opportunity for him both to pivot to a more serious approach on foreign policy, and to provide the kind of specifics that people are looking for from each of the candidates," Josh Block, president and CEO of the Israel Project and a former AIPAC spokesman, told NPR.

Rival candidate Ohio Gov. John Kasich and Speaker of the House Paul Ryan gave speeches to AIPAC before Trump on Monday, and earlier in the day Democratic candidate and former secretary of state Hillary Clinton made a jab at Trump during her pro-Israel speech at AIPAC.

"Yes, we need steady hands,” Clinton said, Politico reported. “Not a president who says he’s neutral on Monday, pro-Israel on Tuesday and who knows what on Wednesday because everything’s negotiable. Well, my friends, Israel’s security is nonnegotiable.”

Before taking the stage at AIPAC, Trump announced a highly anticipated, partial list of his foreign policy advisers: counterterrorism expert Walid Phares, energy consultant George Papadopoulos, former Defense Department inspector general Joe Schmitz, managing partner of Global Energy Capital Carter Page and former Lt. Gen. Keith Kellogg, according to CNN.