"First of all for one administration to tear up an agreement that a previous administration made would be unprecedented," Brennan claimed in an interview with the BBC aired on Wednesday.
He added, "So I think it would be the height of folly if the next administration were to tear up that agreement.”
Iran and the Group 5+1 (Russia, China, the US, Britain, France and Germany), reached the comprehensive nuclear deal, known as the Joint Comprehensive Plan of Action (JCPOA), in July 2015 and implemented it in January 2016.
In a speech to the pro-Israeli lobby group AIPAC (American Israel Public Affairs Committee) in March, Trump declared that his "number-one priority” would be to "dismantle the disastrous deal with Iran."
After Trump's winning the election, Iran’s Foreign Minister Mohammad Javad Zarif said that Iran expects the new US administration respect the nuclear deal.