Blinken says nuclear talks with Iran 'cannot go on indefinitely'

US Secretary of State Antony Blinken said on Thursday that nuclear talks with Iran "cannot go on indefinitely" but that Washington was "fully prepared" to continue negotiations.

"We're committed to diplomacy, but this process cannot go on indefinitely... we look to see what Iran is ready to do or not ready to do and remain fully prepared to return to Vienna to continue negotiations," Blinken said during a visit to Kuwait on Thursday.

"The ball remains in Iran's court."

It comes after Iran's supreme leader's declaration Tehran would not accept Washington's "stubborn" demands in talks to revive a 2015 nuclear deal and said the United States had failed to guarantee that it would never abandon the pact again.

Also read| Iran's Khamenei blames 'cowardly' United States for pause in nuclear talks

Since April 9, Tehran and six world powers have been in talks to revive the nuclear pact ditched three years ago by then U.S. President Donald Trump, who argued it favoured Iran.

The sixth round of indirect talks between Tehran and Washington adjourned on June 20, two days after hardline cleric Ebrahim Raisi was elected president of the Islamic Republic. Parties involved in the negotiations have yet to announce when the next round of negotiations will resume.

Like Khamenei, Raisi has backed the revival of the nuclear pact but officials have said that his government might adopt "a hardline" approach. Khamenei, not the president, has the last say on Iran's state matters, including the nuclear policy.

Iranian and Western officials have said significant gaps remained to reinstate the deal, under which Iran agreed to curb its nuclear program to make it harder to obtain fissile material for a weapon in return for relief from tough sanctions. Iran says it has never sought nuclear weapons and never would.

Harsh sanctions reimposed by Trump since 2018 have prompted Tehran to violate the deal's limits. However, Tehran says its nuclear steps are reversible if Washington lifts all sanctions.

Biden seeks to reinstate and eventually broaden the pact to put more limits on Iran’s nuclear work and its missile development and constrain its regional activities.

(With inputs from agencies)