Among those who are said to have warned Trump that the war could be protracted are Vice President JD Vance and Secretary of State Marco Rubio, WSJ's sources say.
The background is that the advisers see a risk that the Iranian regime may continue to resist the US blockade and other military pressure.
The information contradicts Trump's previous statement that he believes the Iran war will be over after the US midterm elections in November this year.
"I believe the war will end immediately after the election," he told reporters on Wednesday, claiming that Iran "cannot hold out any longer."
