"We ... land on top of it and we took over the ship. We took over the cargo, took over the oil. It's a very profitable business," Trump said on Saturday while addressing a rally in Florida.
As the crowd cheered, he said, "We're like pirates. We're sort of like pirates. But we're not playing games."
After American forces intercepted two tankers said to be transporting Iranian crude, Iran reacted strongly on Tuesday, branding the move "armed robbery on the high seas" and accusing Washington of breaching international law.
Foreign Ministry spokesperson Esmaeil Baghaei said the operation effectively endorsed piracy.
He described it as "the outright legalisation of piracy and armed robbery on the high seas". Writing on X, Baghaei added that the world was witnessing "the return of the pirates", alleging that US authorities were cloaking what he called unlawful seizures in legal justifications.NDTV reported.
Iran has blocked nearly all ships passing through the Strait of Hormuz apart from its own since the start of the war. Trump has imposed a separate blockade of Iranian ports.