Iran issued a warning on Thursday of a "harsh and regretful" retaliation following a deadly Israeli assault on Iranian military facilities last Saturday, according to local media.
Israel and Iran have engaged in a series of tit-for-tat military strikes, part of broader Middle East warfare set off by relentless Israeli attacks on Gaza.
Meanwhile, Israeli intelligence suggests Iran is preparing to attack Israel from Iraqi territory in the coming days, possibly before the U.S. presidential election on Nov. 5, Axios reported on Thursday, citing two unidentified Israeli sources.
Israeli warplanes carried out the strikes in what Tel Aviv said was retaliation for Tehran's Oct. 1 missile barrage, which Iran had in turn described as a reprisal for the killing of Iran-backed leaders and a Revolutionary Guards commander.
Since the attacks on Oct. 26, Israel has warned Iran against retaliating, while Tehran, stating it does not seek war, vowed to respond.
"The recent action of the Zionist regime in attacking parts of our country was a desperate move and the Islamic Republic of Iran will give it a harsh and regretful response," said Mohammad Mohammadi Golpayegani, a senior aide to supreme leader Ayatollah Ali Khamenei, quoted by Tasnim news agency.
He praised Iran's air defense performance in "preventing the entry of the Zionist regime fighters into the territory" and said damage from the strikes was "minimal."
Golpayegani is an influential cleric acting as the head of the office of Khamenei, who has the final say in all matters of the state.
After the strikes, Israeli Prime Minister Benjamin Netanyahu said they "hit Iran's defense capabilities and missile production."
Iran's armed forces said the attack killed four military personnel and caused "limited damage" to a few radar systems. Iranian media said a civilian was also killed.
Also on Thursday, General Hossein Salami, head of the Islamic Revolutionary Guard Corps, a branch of Iran's military, warned of an "unimaginable" response to Israel.
"Israel has reached the stage of collapse and these days it acts blindly and without abiding to any rules it commits every crime," he added, according to Tasnim.
A spokesperson for Iran's Foreign Ministry said on Monday Tehran would "use all available tools" to respond to the Israeli strikes.
The Iranian attack is expected to be carried out from Iraq using a large number of drones and ballistic missiles, according to the Axios report on Thursday.
The report said that carrying out the attack through pro-Iran groups in Iraq could be an attempt by Tehran to avoid another Israeli attack against strategic targets in Iran.