Iran's state TV reported they would hold talks with US only with the permission of Ayatollah Ali Khamenei

Iran's intelligence minister has said Tehran and Washington could hold talks only if the United States ended its sanctions and Iran's top authority, Ayatollah Ali Khamenei, gave his approval, state news agency IRNA reported on Thursday.

"Holding talks with America can be reviewed by Iran only If (U.S. President Donald) Trump lifts the sanctions and our supreme leader gives permission to hold such talks," Mahmoud Alavi said late on Wednesday.

"Americans were scared of Iran's military power, that is the reason behind their decision to abort the decision to attack Iran."

Trump said last month that he had aborted a military strike to retaliate for Iran's downing of an unmanned U.S. drone over the Strait of Hormuz on June 20 because it could have killed 150 people, and signalled that he was open to talks with Tehran.

Tehran said the surveillance drone had been shot down by an Iranian surface-to-air missile in Iranian airspace, while Washington said it had been in international airspace.

Tension has spiked between Tehran and Washington since last year, when Trump quit a 2015 nuclear deal between Iran and six powers and reimposed sanctions that had been lifted under the pact in return for Tehran curbing its sensitive nuclear work.

In reaction to U.S. sanctions, which have notably targeted its main foreign revenue stream in the shape of crude oil exports, Iran has scaled back its commitment to the deal. It said on Wednesday that it would boost its uranium enrichment after July 7 to whatever levels it needs beyond the cap set in the agreement.

The European Union has urged it to stick to the terms of the deal, but Tehran has said its commitment will gradually decrease until Britain, France and Germany can ensure that it benefits financially from the accord - Iran's main incentive for signing up to it.