An Iranian proposal so far rejected by United States President Donald Trump would open shipping in the Strait of Hormuz and end the US blockade of Iran while leaving talks ​on Iran’s nuclear programme for later, a senior Iranian official said on Saturday.

Four ‌weeks since the US and Israel suspended their bombing campaign against Iran, no deal has been reached to end a war that has caused the biggest disruption ever to global energy supplies.

Iran has been blocking ​nearly all shipping from the Gulf apart from its own for more than two ​months. Last month, the US imposed its own blockade of ships from ⁠Iranian ports.

Trump said on Friday that he was “not satisfied” with Iran’s latest proposal, without detailing which elements he opposes.

“They’re asking for things that I can’t agree to,” he ​told reporters at the White House.

Washington has repeatedly said it will not end the war without a deal that prevents Iran from ever obtaining a nuclear weapon, the primary aim Trump cited when he launched the ​strikes in February in the midst of nuclear talks. Iran says its nuclear programme is ​peaceful.

Speaking on condition of anonymity to discuss confidential diplomacy, the senior Iranian official said Tehran believed its ‌latest proposal ⁠to shelve nuclear talks for a later stage was a significant shift aimed at facilitating an agreement.

Under the proposal, the war would end with a guarantee that Israel and the US would not attack again. Iran would open the strait and the US would ​lift its blockade.

Future talks ​would then be ⁠held on curbs to Iran’s nuclear programme in return for the lifting of sanctions, with Iran demanding Washington recognise its right to enrich ​uranium for peaceful purposes, even if it agrees to suspend it.

“Under this ​framework, negotiations ⁠over the more complicated nuclear issue have been moved to the final stage to create a more conducive atmosphere,” the official said.

Reuters and other news organisations have already reported over the past week that Tehran was proposing to reopen the strait before nuclear issues were resolved; the official confirmed that this new timeline has now been spelt out in a formal proposal conveyed ​to the US through mediators.