President Donald Trump has said the United States could stop attacking Iran within two to three weeks and that a deal is not necessary to end a war that has disrupted energy supplies and shaken the global economy.

His comments came as Iranian Minister of Foreign Affairs Abbas Araghchi told Al Jazeera on Tuesday that no negotiations are going on with Washington despite direct and indirect exchanges of messages, nearly five weeks after the US and Israel began attacking Iran.

Trump, who previously claimed that Iran was engaged in negotiations and “begging” for a deal, appeared to change his tune on Tuesday on the alleged diplomatic drive, saying the US would be “leaving very soon”.

“Iran doesn’t have to make a deal, no,” he said when asked by reporters at the White House if successful diplomacy was a prerequisite for the US to wind down the conflict, adding that it could be “maybe two weeks, maybe three” until the exit.

“When we feel that they are, for a long period of time, put into the Stone Ages and they won’t be able to come up with a nuclear weapon, then we’ll leave,” he said.

Iran has always maintained that its nuclear activities are peaceful and that it has never sought to produce a nuclear weapon.

Trita Parsi, a foreign policy expert on Iran at the Quincy Institute, told Al Jazeera that Trump’s statements should be treated with caution. He noted that it would not be “as easy for Trump to just walk out” of a conflict that has spread across the region and killed thousands of people – mostly in Iran and Lebanon, where Israel has launched a ground invasion in conjunction with aerial bombardment – including many civilians.

“Remember, at first they said that this war would be over in four days. Then, three weeks ago, they said it would take three weeks. Three weeks have passed, and now we hear that it’s two to three weeks,” Parsi said.

“The timeline just keeps on being extended because, at the end of the day, the United States is no longer in control of this war”, which has now turned into a “debacle”, he added.

“It would be much better for Trump to just end it as quickly as possible through real negotiations. Not these types of coercive measures that have been tried so far. Otherwise, three weeks from now, we’re likely going to hear that it’s going to take another three weeks.”

‘Go get your own oil!’

Trump’s comments came as domestic petrol prices jumped past an average of $4 a gallon (3.8 litres) as a result of Iran’s attacks on Gulf oil facilities and its continued squeezing of fuel supplies through the Strait of Hormuz, a vital waterway through which one-fifth of the world’s oil and liquified natural gas passes.

But with the war hitting new levels of intensity, Trump has continued to lash out at allied countries that have refused calls for military help to secure freedom of navigation through the Strait of Hormuz.

In a post on Truth Social, the US president took aim at countries, “like the United Kingdom”, which have “refused to get involved in the decapitation of Iran”, telling them to either buy US fuel or get involved in the rapidly escalating war.

“You’ll have to start learning how to fight for yourself, the U.S.A. won’t be there to help you anymore, just like you weren’t there for us. Iran has been, essentially, decimated. The hard part is done. Go get your own oil!” he said.

Earlier, US defence chief Pete Hegseth also highlighted the UK’s reticence about joining the war, saying that “last time I checked, there was supposed to be a big, bad Royal Navy that could be prepared to do things like that as well”.

UK Defence Secretary John Healey addressed the criticism, insisting during a trip to Qatar that his country remained a key ally of the US.

In a separate post on Truth Social, Trump had also hit out at France for being “VERY UNHELPFUL”, in particular in not letting “planes headed to Israel, loaded up with military supplies, fly over French territory”.

President Emmanuel Macron’s office noted that its position, including not authorising the use of French bases for attacks on Iran, had been clear from the get-go.

“We are surprised by this tweet. France has not changed its position since day one [of the conflict] and we confirm this decision,” it said.

Parsi said Trump was “trying to create a narrative of success” by saying that opening the Strait of Hormuz is not part of the US objective in the war on Iran. But at the same time, the US president has shown frustration that European countries are unwilling to help him reopen the important waterway.

“The US has the largest and most powerful navy in the world. If the US cannot do it, what difference can the French make and other Europeans going in?” he asked, predicting that Iran “will continue to control the Strait of Hormuz, and will probably continue to shoot at it”.

Parsi also noted that Trump’s claim that he wanted to send Iranians back to the “Stone Age” was “essentially the Israelisation of America’s war aims”.

“This is how the Israelis are conducting the war. They are not looking for any strategic objective beyond the fact that they just want to make sure that their neighbours are as weak as possible, and every two to three years, they bomb them again.

“This is a ‘mowing the lawn‘ strategy,” he added, referring to Israel’s periodic attacks against Palestinians in recent decades.

In an interview with a US broadcaster on Monday, Israeli Prime Minister Benjamin Netanyahu, who is wanted by the International Criminal Court on war crimes charges over Israel’s genocidal war on Gaza, argued that the war on Iran was “definitely beyond the halfway point … in terms of missions, not necessarily in terms of time”.

“But I don’t want to put a schedule on it,” he added.