US President Donald Trump responded on Sunday to threats from Iranian Supreme Leader Ayatollah Ali Khamenei, who warned the United States earlier that if “they start a war, this time it will be a regional war."

"We have the biggest, most powerful ships in the world over there... hopefully, we'll make a deal. If we don't make a deal, then we'll find out whether or not he was right," Trump said in a conversation with reporters.

His comments came after Khamenei, speaking to the public in Tehran, warned the US against attacking his country.

“The Americans must be aware that if they wage a war this time, it will be a regional war," he said, as quoted by the Associated Press.

“We are not the instigators, we are not going to be unfair to anyone, we don’t plan to attack any country. But if anyone shows greed and wants to attack or harass, the Iranian nation will deal a heavy blow to them," added Khamenei.

Trump said on Saturday night that Iran is “seriously talking" with the US, adding that he hopes Iran accepts a deal which sees it giving up its nuclear weapons.

Speaking to reporters aboard Air Force One, Trump was asked about his latest thinking on Iran and reiterated that he has dispatched significant military assets to the region.

“I hope they negotiate something that’s acceptable," he added.

On Friday, Trump hinted that he had given Iran an ultimatum to make a deal with the US.

Asked whether he is giving Iran a deadline to make a deal before potentially taking military action against them, Trump replied, "Only they know for sure."

To the question of whether he has communicated this to them directly, the President said, "Yeah, I have."

Trump also said, “We’ll see how it all works out, it’s a rough situation… a lot of people are being killed. I can say this, Iran wants to make a deal."

He once again noted the increased US military presence in the region, saying, “We have a tremendously powerful fleet there. We have the most powerful ships in the world."

Hours before Trump’s Friday comments, Iranian Foreign Minister Abbas Araghchi said that Iran is prepared to resume nuclear negotiations with the US, but warned that talks cannot proceed while Washington continues to threaten military action.

Araghchi stressed that Iran will not negotiate over its ballistic missile program and said the country is prepared for either outcome. "Iran is ready for both scenarios - war or diplomacy," he said.