WASHINGTON – U.S. President Donald Trump is "committed" to regime change in Iran, Trump's lawyer and confidant Rudy Giuliani said on Saturday. The unusual statement comes just days before Trump will have to make a dramatic decision on the fate of the nuclear deal with the Islamic Republic.

Giuliani, the former New York City mayor, said at an event hosted by an Iranian opposition group in Washington that regime change in Iran is "the only way to achieve peace in the Middle East."

>> Israel hopes Trump scrapping nuclear deal could lead to Iran regime change | Analysis

The president is "as committed to regime change as we are," Giuliani said in his address. Giuliani predicted that Trump will withdraw the United States from the 2015 deal with Iran. "With Secretary of State Mike Pompeo on his right side, and National Security Adviser John Bolton on his left side, what do you think is going to happen to that agreement?" Giuliani asked with a grin.

Giuliani said that regime change in Tehran was "more important than an Israeli-Palestinian deal" and could contribute to reaching such a deal in the future.

Meanwhile, Iran's President Hassan Rouhani warned on Sunday Iran had prepared plans to respond to any to end the nuclear agreement, adding that the U.S. would regret such a decision.

"We have plans to resist any decision by Trump on the nuclear accord," Rouhani said in a speech carried live by state television. "If America leaves the nuclear accord, this will entail historic remorse for it."

While he does not hold an official position within the Trump administration, Giuliani is considered a close adviser to the president, and was recently added to his legal team dealing with the investigation into Russia's involvement in the 2016 election, as well as with the scandal surrounding Trump lawyer Michael Cohen's payments to adult film actress Stormy Daniels.

The group that hosted Giuliani has been accused by critics of being a "front organization" for Mojahedin-e Khalq (MEK), an Iranian opposition group that was designated in the past as a terrorist organization by the United States.

John Bolton, Trump's new national security adviser is considered to have his own ties to the MEK. A recent article in Foreign Policy included a quote by a congressional aide who said that “Bolton is positively predisposed to the MEK," and that with his appointment, "they will have some access to this White House at the least.”

Trump must decide by May 12 whether to recertify Iran's compliance with the nuclear deal or to reimpose nuclear-related sanctions. He has stated in recent weeks that the deal is a "disaster" and that it never should have been signed. European leaders such as French President Emmanuel Macron and German Chancellor Angela Merkel have lobbied him not to withdraw from the agreement.

Meanwhile, former U.S. secretary of state John Kerry has reportedly met with Iranian Foreign Minister Mohammad Javad Zarif twice over the past two months in an effort to save the deal.