WASHINGTON -- US President Donald Trump said Saturday that he feels reports that Iran's Supreme Leader Ali Khamenei was killed in airstrikes on Saturday are "correct."

"We feel that that is a correct story," said Trump in an interview with NBC News.

However, Iran's Foreign Ministry Spokesperson Esmaeil Baghaei dismissed the reports, telling ABC News in an interview that Khamenei and Iranian President Masoud Pezeshkian are "safe and sound."

In the interview with NBC News, Trump said of Iran's leadership, "The people that make all the decisions, most of them are gone."

Trump also told ABC News in an interview that the White House believes "a lot of" people among Iranian leadership were killed in strikes.

"A lot of it is, yeah. But we don't know all, but a lot of it is. Was a very powerful strike," Trump told ABC News by phone, saying the attack on Iran was going "very well."

Asked about how long the military campaign will last, Trump said: "As long as we wanted to, actually. But it's done such damage already. It's like -- they are incapacitated, essentially -- as long as we wanted to."

Israeli Prime Minister Benjamin Netanyahu said in an address that "signs are growing" that Khamenei has been killed following an Israeli strike on his compound on Saturday.

Khamenei is still alive "as far as I know," Iranian Foreign Minister Abbas Araghchi told NBC News on Saturday morning.