Iran's President Hassan Rouhani Saturday accused arch-foe Israel of acting as a "mercenary" for the United States and seeking to create chaos, vowing Tehran would avenge the assassination of a top Iranian nuclear scientist.
Islamic Republic's supreme leader Ayatollah Ali Khamenei called for the perpetrators to be punished for Friday's killing, while Rouhani stressed the country would seek its revenge in "due time" and not be rushed into a "trap".
Mohsen Fakhrizadeh, who was dubbed by Israel the "father of Iran's nuclear programme", died after being seriously wounded when assailants targeted his car and engaged in a gunfight with his bodyguards outside the capital Tehran on Friday, according to Iran's defence ministry.
The assassination comes less than two months before US President-elect Joe Biden is due to take office, after a tumultuous four years of hawkish US foreign policy in the Middle East under President Donald Trump.
"They are thinking of creating chaos, but they should know that we have read their hands and they will not succeed," Iran's president said in televised remarks.
He pinned the blame for the killing on "the wicked hands of the global arrogance, with the usurper Zionist regime as the mercenary".
Iran generally uses the term "global arrogance" to refer to the United States.
Trump unilaterally withdrew in 2018 from a multilateral nuclear deal with the Islamic republic, which sought to contain its atomic ambitions, and has re-imposed crippling sanctions. But Biden has signaled his administration may be prepared to rejoin the accord.
"This barbaric assassination shows that our enemies are in stressful weeks, during which they feel... their pressure declining, the global situation changing," the Iranian president added.
"The nation of Iran is smarter than to fall in the trap of the conspiracy set by the Zionists," Rouhani said in televised remarks.
- 'Punish the perpetrators' -
The United States slapped sanctions on Fakhrizadeh in 2008 for "activities and transactions that contributed to the development of Iran's nuclear programme", and Israeli Prime Minister Benjamin Netanyahu once described him as the father of Iran's nuclear weapons programme.
Iran has repeatedly denied seeking to develop nuclear weapons.
The New York Times said an American official and two other intelligence officials confirmed Israel was behind the attack, without giving further details.
"Iran's enemies should know, that the people of Iran and officials are braver than to leave this criminal act unanswered," Rouhani added, talking at Iran's weekly Covid-19 taskforce meeting.
"In due time, they will answer for this crime."
Former CIA director John Brennan warned on Friday that the assassination risked sparking a wider conflagration in the Middle East.
"This was a criminal act and highly reckless. It risks lethal retaliation and a new round of regional conflict," Brennan tweeted.
Khamenei called for "punishing the perpetrators and those responsible," in a short statement on his official website, urging that Fakhrizadeh's "scientific and technical efforts ... in all of the fields he was working in" should be continued.
- 'Eye for an eye', or a trap? -
Fakhrizadeh, who headed the defence ministry's reasearch and innovation organisation, died after medics failed to revive him following the attack near Absard city in Tehran province's eastern Damavand county.
Israel has refused to comment on the assassination, but Israeli Channel 12 television reported on Saturday that the level of alert had been raised in its embassies worldwide. A spokeswoman for the Israeli foreign ministry in Jerusalem refused to confirm the report.
Lebanon's Hezbollah militia early Saturday "strongly" condemned the "terrorist operation that led to the martyrdom" of Fakhrizadeh.
The killing of Fakhrizadeh is the latest in a series of killings of nuclear scientists in Iran in recent years that the Islamic republic has blamed on Israel.
Iranian media have given little information regarding his work, but the head of Iran's atomic organisation Ali Akbar Salehi said Saturday they had "good cooperation especially in the field of nuclear defence."
He told state TV that Fakhrizadeh had a Phd in "nuclear physics and engineering" and worked on his thesis with Fereydoun Abbasi-Davani, the former head of the atomic organisation and himself a survivor of an assassination attempt in 2011.
US media reports described Fakhrizadeh as the "No. 1 target of the Mossad", Israel's spy agency, and the "brains behind Iran's nuclear program".
The scientist's death dominated Iranian newspapers on Saturday.
The ultraconservative Kayhan daily wrote: "Eye for an eye: Zionists be ready" and said "the Zionists have time and again proven that they understand no language but that of force."
The reformist Arman-e Melli mirrored Rouhani's speech, saying Iran "must act even more vigilantly than before ... so that we would not walk into the trap of high-tension actions".