“Iran believes in civilian dialogue,” he said. “Directly or indirectly is not important.”

“President Trump can easily stop the war by only one telephone (call) to (the) Israelis,” he said, repeating the Iranian position that talks were impossible while Israeli bombs were striking Iran.

Farahani said that Iran would not countenance halting nuclear enrichment – which Tehran insists is for peaceful purposes – but added that concessions were possible.

“Maybe it can be lower but we don’t stop it,” he said.

In recent days, European powers have joined American and Israeli calls for a ban on enrichment, hardening their positions on the key issue, with France putting forward “a clear position on zero enrichment,” France’s foreign ministry spokesperson Christophe Lemoine told CNN Friday.

Iran says it needs enriched uranium for peaceful purposes, while also manufacturing large quantities of near-weapons-grade material.

Trump’s decision to open a two-week negotiating window before deciding on striking Iran has offered a slim – if improbable – path to a peace deal between Iran and Israel.

Talks took place in Geneva on Friday between the foreign ministers from Iran, Britain, France, and Germany, along with the European Union’s foreign policy chief, the first confirmed face-to-face meeting of its kind since the conflict began.

After days of increasingly aggressive messages from the Trump administration, it has opened the possibility that military action can be averted.

Indeed, Trump’s own camp appears to be starkly divided on whether to pursue direct strikes against Iran.

“If America gets involved in the war,” Farahani said, “there are so many options and all (of) those options are on the table.”

Pro-government protests on Friday on the streets of Tehran saw an outpouring of anger at both Israel and the United States.

A CNN team in Tehran witnessed massive crowds, with protesters waving Iranian, Hezbollah and Palestinian flags and burning US and Israeli flags.

Chants of “death to Israel, death to America” – a staple at such events – rang out, while Iranians spoke of their fury at the bombing campaign.

“Trump, you are threatening my leader,” one woman told CNN, “Don’t you know that my nation believes death is sweeter than honey?”