Iran's Supreme Leader Ayatollah Ali Khamenei has said the US would receive a "slap in the face" if the nuclear deal, currently threatened by the administration of US President Donald Trump, collapses. The Iranian leader warned that Tehran would "shred" the accord if the "other side" tears it up.

Trump, who has been firmly against the landmark nuclear deal signed in 2015, recently refused to re-certify the agreement. Despite strong resistance from the US' European partners, the Trump administration has constantly threatened to pull out of the accord.

Trump said a total suspension of the Obama-era agreement is a "real possibility". Khamenei, who wields the highest authority in Iran, said Trump's remarks do not even deserve a response from him.

"I don't want to waste my time on answering the rants and whoppers of the brute president," said Khamenei, while speaking to a students' gathering in the Iranian capital.

"Trump's stupidity should not distract us from America's deceitfulness ... If the US tears up the deal, we will shred it... Everyone should know that once again America will receive a slap in the face and will be defeated by Iranians," added Khamenei.

Iran and the P5+1 powers – the US, Britain, Russia, France, China and German – signed the nuclear agreement, officially known as the 2015 Joint Comprehensive Plan of Action, after years-long diplomatic wrangling and political negotiations. Iran finally agreed to scale down its nuclear activities in return for easing of economic sanctions on the country.

Except the US under the Trump administration, others support the deal putting the American leadership at odds with its allies.

Khamenei continued: "The European governments have voiced support for the nuclear deal and condemned the US president's remarks. We welcome their stance, but this is not enough to just ask Trump not rip up the nuclear agreement. The nuclear deal is to their benefit. We will not tear up the agreement as long as the other side remains committed."