TEHRAN: Iran's supreme leader Ayatollah Ali Khamenei said Wednesday that experience has shown "trusting the West does not work", as the Islamic republic prepares for a new administration to take power.

Khamenei also blasted the US, which is indirectly involved in Iran's talks with world powers to revive a nuclear deal, of tying its return to the accord to "future" negotiations on Iran's missile programme and regional issues.

The 2015 deal, the signature achievement of outgoing moderate President Hassan Rouhani, gave Iran some relief from international sanctions in exchange for limits on its nuclear programme.

But it was torpedoed in 2018 by then US president Donald Trump, who unilaterally withdrew from the agreement and imposed punishing sanctions.

"Future generations should use this experience," Khamenei told Rouhani and members of his cabinet. "It was made clear during this government that trusting the West does not work."

Rouhani's government has been holding talks with major powers in Vienna since April on bringing Washington back into the agreement, but a deal now seems unlikely until after he hands over to President-elect Ebrahim Raisi early next month.

Raisi has expressed support for the nuclear talks, arguing Iran needs an end to US sanctions.

Iran's ultraconservative camp, which deeply distrusts the United States, has repeatedly criticised Rouhani over the 2015 deal.

Raisi has said his government will support talks that "guarantee national interests", but will not allow negotiations for the sake of negotiations.

   **- 'Future' talks -**

Khamenei said Washington has conditioned its return to the 2015 deal on including "a sentence... that (says) some issues be talked about in the future, or we will have no agreement".

"With that sentence, they want to have an excuse for their next meddlings with the (deal) itself -- missiles and regional issues," his official website quoted him as saying.

One of the major criticisms of the 2015 deal raised by Trump was its failure to address Iran's ballistic missile programme or its alleged interference in regional affairs.

But Tehran has always rejected bringing non-nuclear issues into the agreement, which is known formally as the Joint Comprehensive Plan of Action.

Khamenei also criticised the US for refusing to "guarantee that (it) will not violate the agreement in the future" by pulling out unilaterally, as Trump did in 2018.

"Whenever you postponed issues with agreements with the West or negotiations with the West and America and the like, you were stuck and could not progress," he told the Rouhani government.

"Because they don't help. They are the enemy after all."

Trump's successor Joe Biden has signalled his readiness to return to the nuclear deal and has engaged in indirect negotiations with Iran alongside formal talks with the agreement's remaining parties, Britain, China, France, Germany and Russia.

Iran's chief negotiator Abbas Araghchi said this month that the talks must "await our new administration" as Tehran is "in a transition period".

A sixth round of talks concluded on June 20 and dates for the next round have yet to be fixed.

Rouhani, in office since 2013 and preparing to leave after the maximum two consecutive mandates, had repeatedly promised to achieve sanctions relief before the end of his term.

But earlier in July, he expressed hopes that his successor can clinch a deal to lift sanctions, insisting that from his administration's side, "the work was ready" to be done.