Amid ongoing Western efforts to engage with Iran diplomatically and economically on its rogue nuclear program, a senior Iranian cleric and prayer leader dedicated his weekly Friday sermon to the threat of US military aggression against Iran, saying Iran would easily deliver a “crushing response” to any such attack.

Speaking to a crowd of students at Tehran University Friday, Tehran’s provisional Friday Prayers Leader Ayatollah Ahmad Jannati said, “We are eager for your options on the table.”

He was referring to statements by US and other Western officials, saying that while Western powers would pursue the diplomatic track to prevent Iran from achieving military nuclear capability, other options — such as a military strike — would remain on the table in case diplomacy proved fruitless.

Iran’s “number one option” on the table, according to Jannati, was “Down with the US.”

According to Iran’s Fars News, Jannati said the Iranian military would be prepared to issue a crushing response in the event of an American strike.

Noting that masses of Iranians had attended rallies earlier this month marking the 35th anniversary of the country’s 1979 Islamic Revolution, Jannati said that “the message of the Iranian people was that they are not afraid of your options on the table.”

Meanwhile Friday, at least two US aerospace companies applied for export licenses to sell passenger airplane parts to Iran in light of an easing of sanctions that is part of the interim nuclear deal between Tehran and Western powers.

Both Boeing and General Electric are reportedly seeking access, for the first time since 1979, to the Islamic Republic, according to industry insiders cited by Reuters.

Iran and Western powers winded down nuclear talks on Thursday, having arrived at a framework agreement for future negotiations — but with little concrete progress.

However, a Western diplomat revealed Friday that European Union foreign policy chief Catherine Ashton would be traveling to Iran in March to lead negotiations there.

The diplomat, who said Ashton would visit Tehran March 9-10, demanded anonymity because his information was confidential.

In a joint statement at the end of the three-day talks, officials for both sides said they would meet again in Vienna on March 17, continuing a process likely to take at least six months and probably longer.

Expectations had been modest as the talks started Tuesday. The announcement of an agreement on future talks appeared aimed in part to raise hopes that the negotiations had a chance to succeed.

The Associated Press contributed to this report.