TEHRAN: Iran's supreme leader Ayatollah Ali Khamenei on Saturday (Nov 28) retaliate for the killing of the country's top nuclear scientist, raising the threat of a new confrontation with the West and Israel in the remaining weeks of Donald Trump's presidency.
Khamenei pledged to continue the work of Mohsen Fakhrizadeh, who Western and Israeli governments believe was the architect of a secret Iranian programme to make weapons.
Friday's killing, which Iran's president was swift to blame on Israel, could complicate any efforts by President-elect Joe Biden to revive a detente with Tehran that was forged when he was in Barack Obama's administration.
Trump pulled Washington out of the 2015 international nuclear pact agreed between Tehran and major powers.
Khamenei, who is Iran's top authority and who insists the country has never sought nuclear arms, said on Twitter that Iranian officials must take up the task of "pursuing this crime and punishing its perpetrators and those who commanded it".
He called Fakhrizadeh a "prestigious nuclear and defence scientist" and said he was "martyred by the hands of criminal and cruel mercenaries".
"This unparalleled scientist gave his dear and valuable life to God because of his great and lasting scientific efforts, and the high prize of martyrdom is his divine reward," he added.
Iranian President Hassan Rouhani told a televised cabinet meeting on Saturday Iran would respond "at the proper time".
"Once again, the evil hands of Global Arrogance and the Zionist mercenaries were stained with the blood of an Iranian son," he said, using terms officials employ to refer to Israel.
Israel's N12 news channel said Israeli embassies had been put on high alert after the Iranian threats of retaliation.
Israel has declined to comment on the killing of Fakhrizadeh and an Israeli Foreign Ministry spokesman said the ministry did not comment on security regarding missions abroad.
The White House, Pentagon, US State Department and CIA have also declined to comment on the killing, as has Biden's transition team. Biden takes office on Jan 20.
"Whether Iran is tempted to take revenge or whether it restrains itself, it will make it difficult for Biden to return to the nuclear agreement," Amos Yadlin, a former Israeli military intelligence chief and director of Israel's Institute for National Security Studies, wrote on Twitter.
Fakhrizadeh was "martyred" 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 ministry said that the scientist, who headed its research and innovation organisation, died after medics failed to revive him.
"REMEMBER THAT NAME"
Germany, one of the signatories to the nuclear pact, called for restraint on all sides to avoid derailing any future talks.
"Definitely Iran will retaliate. When and how depends on our national interests. It might happen in the coming days or weeks, but it will happen," a senior Iranian official told Reuters.
He pointed to Iran's retaliatory missile attacks in January on an Iraqi base where US forces were stationed, days after a U.S. drone strike in Baghdad killed top Iranian military commander Qassem Soleimani. No US troops were killed in the action.
"The martyrdom of Fakhrizadeh will accelerate our nuclear work," said Fereydoon Abbasi, the former head of Iran's Atomic Energy Organisation, who survived an assassination attempt in 2010.
At least four scientists were killed between 2010 and 2012 in what Tehran said was a programme of assassinations aimed at sabotaging its nuclear energy programme. Iran has always denied pursuing nuclear weapons, saying its aims are only peaceful.
Fakhrizadeh was thought to have headed what the UN International Atomic Energy Agency (IAEA) and the US intelligence services believe was Iran's nuclear arms programme.
He was the only Iranian scientist named in the IAEA's 2015 "final assessment" of open questions about Iran's nuclear programme. It said he oversaw activities "in support of a possible military dimension to (Iran's) nuclear programme".
Fakhrizadeh was also a central figure in a presentation by Israeli Prime Minister Benjamin Netanyahu in 2018 accusing Iran of continuing to seek nuclear weapons. "Remember that name, Fakhrizadeh," Netanyahu said at the time.
US intelligence services and the IAEA believe Iran halted its coordinated weapons programme in 2003. The IAEA has said it had no credible indications of activities in Iran relevant to the development of a nuclear explosive device after 2009.
The United States deployed US aircraft carrier Nimitz with accompanying ships to the Gulf on Wednesday, shortly before the killing, but a US Navy spokeswoman said the deployment was not related to any specific threats.