Trump has said he thinks Iran's new Supreme Leader Mojtaba Khamenei is alive but "damaged."
Khamenei has not been seen since his selection on Sunday by a clerical assembly.
His first comments were read out by a television presenter on Thursday.
An Iranian official said Wednesday that the newly appointed supreme leader was lightly injured but continuing to operate, after state television described him as war-wounded.
"I think he probably is (alive). I think he is damaged, but I think he's probably alive in some form, you know," Trump said in an interview on Fox News' "The Brian Kilmeade Show."
Khamenei's father, the longtime supreme leader Ayatollah Ali Khamenei was killed February 28 on the first day of the war.