Iranian Supreme Leader Ayatollah Ali Khamenei has threatened to “set fire” to the nuclear deal with world powers “if the threat from the American presidential candidates to tear up the deal becomes operational.”

In that case, “the Islamic Republic will set fire to the deal,” Khamenei said, reacting to comments made last August by presumptive Republican nominee Donald Trump that he would “police that contract so tough they don’t have a chance.” Various Republican presidential contenders who have now dropped out of the race had also spoke out strongly against the nuclear deal, which was reached last year. Democratic candidates Hillary Clinton and Sen. Bernie Sanders (D-Vt.) support the deal.

Iran can expect a possible Republican presidential administration in 2017 to take a harder line in American-Iranian relations than current President Barack Obama.

“The Islamic Republic won’t be the first to violate the nuclear deal. Staying faithful to a promise is a Quranic order,” said Khamenei, Reuters reported, citing Iranian state media.

The supreme leader also noted that “the nuclear deal has holes which, if they were closed, would reduce or cancel its disadvantages. Some think that we can get along with the Americans and solve our problems. This is an incorrect idea and a delusion.”