Iran's Supreme Leader Ayatollah Ali Khamenei has hit back at US President Donald Trump's recent comments on "obliterating" Iran's nuclear research sites, local Hamshahri reported on October 20.

Khamenei asked rhetorically, "What business is it of yours if a country has a nuclear industry to tell them what they should and shouldn't do," during a meeting with unsuspecting sportspeople and scientific Olympiad medallists in Tehran.

"The US president travelled to occupied Palestine [Israel] and said a bunch of empty words with pretentiousness trying to encourage disappointed Zionists and give them morale," Khamenei said.

He added Trump tried with "disgraceful behaviour" and many lies about the region, Iran and the Iranian nation to show himself capable to Zionists.

"But if he has capability, let him go calm the millions of people who are chanting slogans against him in all US states," he said.

"In the Gaza war, America is undoubtedly the main partner in the crimes of the Zionist regime, just as the US president himself admitted that we were working with this regime in Gaza," Khamenei said.

"Even if he hadn't said this, it was clear because the facilities and weapons that were poured on the heads of the defenceless people of Gaza during this war belonged to America."

Khamenei called Trump's claim about America's war against terrorism another example of false statements.

"More than 20,000 children and infants were martyred in the Gaza war. Were they terrorists?" Khamenei said. "The terrorist is America, which creates ISIS and throws it at the region's life," referring to the current leadership of Syria stemming from Islamic State.

The killing of about 70,000 people in the Gaza war and the martyrdom of more than 1,000 Iranians in the 12-day war are clear evidence of the terrorist nature of America and the Israeli regime, according to Khamenei.

"In addition to the blind killing of people, they assassinated our scientists such as Mohammad-Mehdi Tehranchi and Fereydoon Abbasi and were proud of this crime, but they should know that they cannot assassinate science," he said.

Khamenei referred to Trump's words claiming to have bombed and destroyed Iran's nuclear industry.

"There is no problem, you can keep thinking that, but what business is it of yours if a country has a nuclear industry to tell them what they should and shouldn't do?" Khamenei said. "What does it have to do with America whether Iran has nuclear facilities and industry or not? These interventions are illegitimate, wrong and bullying."

Khamenei referred to nationwide protests of 7mn people against Trump in various US states and cities.

"If you have so much capability, instead of spreading lies, interfering in the affairs of other countries and actions such as building military bases in them, calm these millions of people and return them to their homes," he said.

Khamenei called America the terrorist and true manifestation of terrorism, also calling Trump's claim of supporting the Iranian people a lie.

"America's secondary sanctions, which many countries also accompany out of fear, are against the Iranian nation, therefore you are an enemy of the Iranian nation, not its friend," he said.

Khamenei referred to Trump's expression of readiness for a deal.

"He says I am a dealer, while if a deal is accompanied by bullying and its result is predetermined, it is not a deal but imposition and bullying," Khamenei said. "The Iranian nation will not accept imposition."

"You start wars. America is a warmonger and in addition to assassination, it starts wars," he said. "Otherwise, what are all these US military bases in the region for? What are you doing here? What does this region have to do with you? The region belongs to its own people and war and death in this region are caused by America's presence."

Khamenei called Trump's positions wrong and in many cases lies and indicative of bullying.

"Although bullying affects some countries, with God's grace it will never affect the Iranian nation," he said.