Iran’s stranglehold on the Strait of Hormuz that has impacted economies around the world, including the UK’s, must end as part of any deal to end the war, Donald Trump has said.
The US president said the strategic Gulf waterway had to “open immediately” if an agreement was to be reached.
Despite previously only giving Tehran “a limited period of time” to strike a deal after calling off fresh attacks, Mr Trump said he was now “in no hurry”.
But he maintained the threat of further military action, warning the US would “do some things that are a little bit nasty” if current talks failed.
Meanwhile, Chinese leader Xi Jinping and Russian President Vladimir Putin meeting in Beijing have accused the US and Israel of breaking international law in attacking their ally Iran and stated their “resolute opposition to hegemonism and unilateralism”.
The criticism came just days after Mr Trump’s visit to China.
The Strait of Hormuz has become the focus of a stand-off between the US and Iran, with clashes testing the fragile Middle East ceasefire.
Since the start of the conflict Tehran has virtually shut off the vital shipping route, sending petrol prices soaring, and led the US to impose its own blockade of the country’s ports.
In the latest confrontation in the area, US marines boarded and diverted an Iranian-flagged oil tanker suspected of trying to get through.
Referring to any prospective deal, Mr Trump said: “The strait would have to open immediately.”
But he added: “I’m in no hurry.”
The president told reporters: “We’re in the final stages of Iran. We’ll see what happens. Either have a deal or we’re going to do some things that are a little bit nasty, but hopefully that won’t happen.”
Speaking later at a graduation ceremony at the US Coast Guard Academy in Connecticut, Mr Trump said of Iran: “Everything’s gone. Their navy’s gone. Their air force is gone. Just about everything.
“The only question is, do we go and finish it up, or are they going to be signing a document? Let’s see what happens.”
He went on: “People don’t want them to have a nuclear weapon, and they will not have a nuclear weapon, and they want to make a deal so badly.”
Meanwhile, Iran’s hardline Islamic Revolutionary Guard Corps (IRGC) has warned it will widen the war “beyond the region” if military strikes against the country are renewed and its “crushing blows will bring you to ruin in places you cannot even imagine”.
