President Donald Trump on Saturday said that an agreement to end the war with Iran will be signed on Sunday, followed by the opening of the Strait of Hormuz, hours after Iranian state media reported that the country remained cautious about the timing.

“The Deal is scheduled to get signed tomorrow, and immediately after it is signed, the Hormuz Strait is OPEN TO ALL,” Trump wrote in a Truth Social post.

Trump also suggested that the U.S. will work with Iran to remove enriched uranium from the country at an undetermined date.

“At the appropriate time, when all is calm, we will go in and get the Nuclear Dust, buried deep under the powerful sunken granite mountains,” he said.

“We look forward to working with Iran, and the entire Middle East, long into the future,” he added.

However, earlier in the day, Iranian Foreign Ministry spokesperson Esmaeil Baghaei was quoted by state media as saying that caution was needed regarding the timing of signing any deal.

“We will have to wait and see about the exact date of the signing of the memorandum of understanding, although it will not be tomorrow,” state media reported. “The possibility of this happening in the coming days cannot be ruled out. However, due to the hesitation of the other side, we must be cautious in making any comments about this process.”

Trump’s Saturday post concluded with what appeared to be a veiled threat against Iran if its leaders don’t comply with U.S. demands.

“Hopefully, this process will all work out quickly, easily, and smoothly. If it doesn’t, we have the ultimate alternative, hopefully never to be used again!”

The White House did not immediately respond to a CNBC request for clarification on Trump’s remarks.

Earlier on Saturday, Pakistani Prime Minister Shehbaz Sharif said the U.S. and Iran are “closer to a peace deal than ever before,” indicating a finalization in the next 24 hours with “technical level talks next week.” Trump reposted those comments on his Truth Social account.

Pakistan’s Deputy Prime Minister Mohammad Ishaq Dar also said he discussed the impending peace agreement in a call with Saudi Arabia’s foreign minister, Prince Faisal bin Farhan.

“They welcomed the U.S.–Iran negotiations in their final stage, with the electronic signing ceremony scheduled for tomorrow, and expressed the hope that this important development will contribute to lasting peace and stability in the region,” the deputy PM said in a post on X. A senior Trump administration official said Friday that the U.S. is not “100%” confident that the agreement they reached will be signed.

In its current state, the agreement would guarantee “long-term peace in the region” and reward Iran with “significant” economic relief.

— CNBC’s Kevin Breuninger, Azhar Sukri and Reuters contributed to this report.