Iran has presented a 10-point plan as the basis for talks, but it includes maximalist positions previously rebuffed by Washington.

Here are the key issues:

- Control over the Strait of Hormuz -

In retaliation for the war launched by the United States and Israel on February 28, Iran effectively paralysed the strait, through which part of the world's oil, gas and fertiliser passes, battering the global economy.

Tehran has agreed to temporarily reopen the route -- claimed as a victory by US President Donald Trump -- but has demanded control of the strait in its plan.

It's unclear how Iranian sovereignty over the strait would work.

Iran and Oman -- the other country bordering the waterway and previous mediator between Washington and Tehran -- both said in recent days that talks were held to agree a peacetime protocol that would supervise maritime traffic through the strait.

Both Washington and Tehran have said they are considering a plan to impose tolls, but it was unclear if the Oman-Iran mechanism would involve fees.

According to an Iranian diplomatic source, the new mechanism provides for a passage fee organised in partnership with Oman. The Sultanate of Oman has not commented on this point.

Other than Omani tankers, crossings through the strait in recent days appeared to have used an Iranian-approved route just off the country's coast near Larak Island, which Lloyd's List has dubbed the "Tehran Toll Booth".

Before the ceasefire, Tehran had warned it was preparing to impose new operating conditions in the route, with the powerful Revolutionary Guards saying the strait "will never return to its former status, especially for the US and Israel".

- Sanctions relief -

Iran, under crippling sanctions over its nuclear programme, has reiterated its demand for complete relief in its plan.

Trump had reimposed punishing sanctions in 2018 during his first term in office after he pulled the United States out of a landmark nuclear deal with Iran that offered sanctions relief in return for strict enrichment curbs and supervision.

The sanctions have choked essential trade services such as banking, while scaring off companies from doing business in Iran.

They contributed to economic pains that sparked protests in December that turned into mass demonstrations against the Islamic republic in January before they were met with a violent crackdown.

Trump had said he would come to the aid of protesters and suggested the war would make way for the toppling of the Islamic republic, but human rights issues or dismantling the ruling system were not part of the ceasefire talks.

The US and Israel had previously insisted on curbs on Iran's long-range ballistic missile programme and an end to the country's support to militant groups such as Hezbollah in Lebanon or the Houthis in Yemen.

There is no mention of either issue in the 10-point Iranian ceasefire plan.

- Uranium enrichment -

Trump justified the war by accusing Tehran of rushing towards the completion of an atomic weapon, an assertion not backed by the UN nuclear watchdog and which Iran has denied.

Iran's plan would require Washington to accept its uranium enrichment programme for civilian purposes.

But Trump again insisted on Wednesday that Iran would cease enrichment, and proposed a solution to retrieve its 440-kilogram stockpile of highly enriched uranium, which was targeted in US bombing last June and is believed to have been buried.

"There will be no enrichment of Uranium, and the United States will, working with Iran, dig up and remove all of the deeply buried (B-2 Bombers) Nuclear 'Dust,'" he posted on his Truth Social platform, apparently referring to the aftermath of US strikes against Iran's nuclear facilities last year.

The United States and Israel launched strikes on Iran in the midst of negotiations in which Washington demanded Iran hand over its stockpile of enriched uranium and stop any further enrichment.

Tehran has insisted since 2003 it is not seeking a nuclear weapon but has a right to enrich uranium for civilian nuclear energy purposes.

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