US President Donald Trump said on Sunday he had told his representatives not to rush into any deal with Iran, as his administration played down hopes of an imminent breakthrough in the three-month-old war that had been raised a day earlier.

The US blockade on Iranian ships in the Strait of Hormuz would “remain in full force and effect until an agreement is reached, certified, and ‌signed,” Trump wrote on Truth Social. “Both sides must take their time and get it right,” he added.

There was no immediate response from Iran’s government. But Tasnim news agency, which is linked to Iran’s Revolutionary Guards, said the US was still obstructing parts of a potential deal, including Tehran’s demand for the release of frozen funds.

A day earlier, Trump said Washington and Iran had “largely negotiated” a memorandum of understanding on a peace deal that would reopen the Strait of Hormuz, which before the conflict carried one-fifth of global oil and liquefied natural gas shipments.

The two sides remain at odds on several difficult issues, such as Iran’s nuclear ambitions, Israel’s war in Lebanon with the Iranian-backed Hezbollah militia and Tehran’s demands for the lifting of sanctions and the release of tens of billions of dollars of Iranian oil revenues frozen in foreign banks.

Working out deal’s details

A senior Trump administration official told reporters an agreement would not be signed on Sunday, saying that the Iranian system ⁠did not move fast enough. But he outlined what he said were the latest contours of what was being negotiated.

The official, speaking on the condition of anonymity, said Iran had agreed “in principle” to open the Strait of Hormuz, in exchange for the United States lifting its naval blockade, and to dispose of Tehran’s highly enriched uranium.

He said the US understood Iran’s Supreme Leader Ayatollah Mojtaba Khamenei had endorsed the broad template of the deal.

There was no immediate confirmation from Iran or elaboration on what an “in principle” agreement meant.

The US official said Washington envisioned first re-opening the strait and lifting the US naval blockade. Negotiating the details of the nuclear measures would take more time, he said.

He pushed back on suggestions that Iran has not accepted disposing of its stockpiled enriched uranium. “It’s a question about how,” the official said.

A second senior administration official said on Sunday that the proposed framework would give negotiators 60 days to reach a final deal.

Iranian sources had told Reuters that in future stages, “feasible formulas” could be found to resolve the dispute over its highly enriched uranium stockpile, including diluting the material under the supervision of the U.N. nuclear watchdog.

Iran has long denied US and Israeli accusations that it is pursuing nuclear weapons and says it has a right to enrich uranium for civilian purposes, although the purity it has achieved far exceeds that needed for power generation.

Deal draws out US critics

Trump, whose approval ratings have been hit by the war’s impact on US energy prices and who has faced congressional efforts to curb his war powers, has ‌repeatedly played up ⁠the prospect of an agreement to end the conflict that the US and Israel started on February 28. A tenuous ceasefire has been in place since early April.

Oil prices hit two-week lows to kickstart the week with Brent crude futures down over 4% to $98.83 a barrel — the first time it has dipped below $100 in intraday trading since early May — while US West Texas Intermediate was at $92.03 a barrel, also down over 4%.

As details of the possible agreement emerged over the weekend, critics including former Secretary of State Mike Pompeo and Democratic lawmakers argued that it offered little beyond the 2015 Iran nuclear deal negotiated by former President Barack Obama, from which Trump withdrew during his first term.

Chris Van Hollen, a Democratic member of the Senate Foreign Relations Committee, said the deal’s reported outlines would amount to little more than “the pre-war status quo” with Iran.

“I think ⁠this was a blunder,” Van Hollen said on the “Fox News Sunday” program. “When you’re digging a hole, you should stop digging, and that sounds like maybe what we’re doing finally.”

Trump, who has also faced criticism from hawkish conservatives over his willingness to compromise with Iran, pushed back.

“If I make a deal with Iran, it will be a good and proper one ... So don’t listen to the losers, who are critical about something they know nothing about,” Trump said in a Truth Social post on Sunday.

In another potential stumbling block, an Iranian military adviser to Khamenei said Tehran ⁠had the legal right to manage the Strait of Hormuz, though it was not clear if that meant continuing to decide which ships can go through.

Iran’s Revolutionary Guards said 33 vessels had passed through the strait over the past 24 hours after getting permission from Tehran, still far short of the 140 on a typical day before the war.

Any deal reinforcing the current fragile ceasefire would bring relief to markets but not immediately quell a global energy crisis, which has driven up costs of fuel, fertilizer and food.

Even ⁠if the war ends now, full flows through the strait will not return before the first or second quarter of 2027, the head of the Abu Dhabi National Oil Company said last week.

The US-Israeli bombing of Iran killed thousands of people in Iran before it was suspended in early April.

Israel has also killed thousands more and driven hundreds of thousands from their homes in Lebanon, which it invaded in pursuit of Hezbollah. Iranian strikes on Israel and neighbouring Gulf states have killed dozens.