All officials unanimously believe there will be no negotiations with US at any level, he says.

Iran's supreme leader Ayatollah Ali Khamenei on Tuesday ruled out negotiations with the US, as tensions mount between the arch-foes after Washington blamed Tehran for attacks on Saudi oil installations.

"The policy of 'maximum pressure' against the Iranian nation is worthless and all Islamic Republic of Iran officials unanimously believe there will be no negotiations with the US at any level," he said, quoted on his official website.

The White House said on Sunday that US President Donald Trump could meet Iranian counterpart Hassan Rouhani on the sidelines of the United Nations General Assembly in New York next week.

Tehran and Washington have been at loggerheads since May last year when Trump withdrew from a 2015 nuclear deal and began reimposing crippling sanctions.

Iran responded by scaling back its commitments under the landmark accord, which gave it the promise of sanctions relief in return for curbs on its nuclear programme.

The UN General Assembly debate opens on September 24.