President Donald Trump on Monday said that he ordered military action against Iran because he viewed it as the "last, best chance” to halt the country’s alleged nuclear threat.

"This was our last, best chance to strike, what we're doing right now, and eliminate the intolerable threats posed by this sick and sinister regime," Trump said at the White House.

He also said the U.S. attack on Iran is meeting its goals ahead of schedule but also warned the war could go "far longer" than his initial estimates of about a month.

"We're already substantially ahead of our time projections," Trump said at the White House, adding: "From the beginning we projected four to five weeks, but we have capability to go far longer than that. We'll do it."

He said a central premise of the fight was to prevent Iran from developing a nuclear weapon, which Tehran denied doing, and thwart its long-range ballistic missile ⁠program.

Trump, at an event in the White House East Room, offered his most extensive comments about the war beyond two video messages and a series of brief phone ⁠interviews ‌with reporters ‌over the weekend that offered ⁠sometimes conflicting ‌objectives in the conflict.

Trump said U.S. forces had knocked out ⁠10 Iranian ships ⁠and he expressed confidence about how ⁠the campaign was going.