Iran is capable of producing nuclear weapons and an existential threat could cause a rethink of the Supreme Leader's injunction against them, one of his top foreign policy advisors told Lebanese news outlet Al Mayadeen.

"If the Islamic Republic of Iran faces an existential threat, we would have no choice but to adjust our military doctrine," Former foreign minister Kamal Kharrazi said in an interview with the pro-Tehran channel.

"We already have the technical capabilities to produce weapons; only a religious decree forbidding nuclear weapons prevents us from doing so," he added, referring to a religious decree by the country's ultimate decision maker Ali Khamenei.

Kharrazi heads the Strategic Council on Foreign Relations and has hinted before that Iran could ditch its stated opposition to acquiring nuclear weapons but was offering his first public remarks since Israeli air strikes on Iran on Oct. 26.

Members of the body he leads are by handpicked by Khamenei and its reports and advisories have often presaged major policy shifts by the ruling system.

Iran has maintained that it will not pursue nuclear arms because the 2010 fatwa banned all weapons of mass destruction including nuclear bombs. The decree could potentially be interpreted by Iranian decision-makers as an advisory opinion lacking legal status, however.

Israel launched air strikes on military targets in Iran over the weekend in response to a missile barrage Tehran fired on the Jewish state on Oct. 1.

The attack hit missile facilities and air defense capabilities, killing four Iranian soldiers and a civilian.

Kharrazi told Al Mayadaeen that Iran would seek to expand the reach of weapons. "There’s a possibility that Iran may increase its missile range," he said.

Upping Iran's official rhetoric, all three top leaders of Iran's Islamic Revolutionary Guard Corps on Thursday said a damaging counterstrike to Israel by Tehran was assured.