A senior Iranian official issued fresh threats against President Donald Trump, warning that the United States will not be able to end its conflict with Tehran as easily as it began it.

Ali Larijani, secretary of Iran's Supreme National Security Council, said Washington would come to regret launching the war and vowed that Iran would continue fighting until the United States pays a price for its actions.

"Trump says he is looking for a speedy victory. While starting a war is easy, it cannot be won with a few tweets," Larijani wrote in a post on the social media platform X. "We will not relent until making you sorry for this grave miscalculation. #TrumpMustPay."

Earlier this week, Larijani also warned that Iran's response would continue until the United States faced consequences for its actions, saying Tehran would not back down under military pressure and cautioning that Washington had underestimated Iran's ability to sustain the conflict.

"The Ashura-loving nation of Iran does not fear your paper threats," Larijani wrote. "Even those greater than you could not eliminate the Iranian nation. Watch out for yourself — lest you be eliminated."

In a follow-up post, Larijani repeated the warning, writing that "those greater than you have failed to erase it … so beware lest you be the ones to vanish."

Larijani's latest remarks came after Trump suggested the U.S. had already crippled Iran's military capabilities through a series of strikes on strategic targets.

Trump has said U.S. forces have hit so many sites inside Iran that there is "practically nothing left to target," and insisted the conflict could end "anytime I want it to end."

The exchange reflected intensifying rhetoric between Washington and Tehran as fighting between Iran and a coalition backed by the U.S. and Israel continues to escalate across the region.

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