US President Donald Trump said there had been “some pretty good news” about Iran, suggesting optimism about peace talks to end the war in the Middle East, but he said a ceasefire in ​the conflict may not be extended without a deal by Wednesday.

Iran, hours earlier, had temporarily reopened the Strait of Hormuz following a separate US-brokered ceasefire agreement by Israel and Lebanon.

But subsequent statements from ‌both sides left uncertainty over how quickly shipping might return to normal through the global oil choke point.

Trump, speaking on Air Force One late on Friday, declined to elaborate on what the good news was.

No clarity on direct talks

“It seems to be going very well in the Middle East with Iran,” he told reporters while returning to Washington from Phoenix, Arizona.

“We’re negotiating over the weekend. I expect things to go well. Many of these things have been negotiated and agreed to.

“The main thing is that Iran will not have a nuclear weapon. You cannot ​let Iran have a nuclear weapon, and that supersedes everything else.”

But in sharp contrast, he said he may end the ceasefire with Iran unless a long-term deal to end the war is agreed before it expires on Wednesday, ​adding that a US blockade of Iranian ports would continue.

The war with Iran, which began on February 28 with a US-Israeli attack, has killed thousands and sent oil prices surging ⁠because of the de facto closure of the strait, which until recently carried about a fifth of the world’s oil trade.

Trump has told Reuters there would probably be more direct talks between Iran and the US this weekend.

Some diplomats said ​that was unlikely given the logistics of gathering in Islamabad, where the talks are expected to take place.

There were no signs of preparations early on Saturday for talks in the Pakistani capital, where the highest-level US-Iran negotiations since the 1979 revolution ​ended without agreement last weekend.

A Pakistani source aware of mediation efforts said a meeting between Iran and the US could produce an initial memorandum of understanding, followed by a comprehensive peace agreement within 60 days.

Iran has said all ships crossing the Strait must coordinate with the Islamic Revolutionary Guard Corps, which was not the case before the war.

The Defence Ministry said in a statement quoted by state television that military vessels and ships linked to “hostile forces” — the US and Israel — were still not permitted to pass.

Shipping companies have said they would require clarifications, including about the risk of mines, before vessels moved through the entry point to the Gulf.