JD Vance said the fragile ceasefire with Iran depends on Tehran agreeing to reopen the Strait of Hormuz as part of ongoing de-escalation efforts.

He warned that if Iran does not act in good faith, it will realize that President Donald Trump should not be underestimated.

Vance also said Trump is keen to make progress on Iran and has instructed him and the negotiating team to engage seriously and in good faith to reach a deal.

On Wednesday, Trump said the United States is prepared to resume military action against Iran if no acceptable agreement is reached. In an interview with Sky News, he said returning to fighting would be very easy.

A day earlier, Trump announced a two week mutual ceasefire with Iran, saying it followed an initiative by Pakistani Prime Minister Shehbaz Sharif and was supported by Tehran’s willingness to fully and immediately reopen the Strait of Hormuz safely.

However, Iranian state television said Tehran had set ten conditions for the ceasefire and that Washington had to accept them. These included a commitment to non-aggression, Iranian control over the Strait of Hormuz, continuing uranium enrichment inside Iran, lifting both primary and secondary sanctions, paying compensation, and the withdrawal of U.S. forces from the region.

At the same time, White House spokesperson Karoline Leavitt said the United States achieved its main military goals in Iran within 38 days, noting that the operation had originally been planned to last between four and six weeks.