Iran's UN envoy, Amir Saeid Iravani, says Tehran reserves its right to defend itself and hit any threat coming from Israel "wherever and whenever it deems necessary".
Iran has blamed Israel for a drone attack on a military factory near the central city of Isfahan, vowing revenge for what appeared to be the latest episode in a long-running covert war, the semi-official ISNA news agency reported.
In a letter to the UN chief, Iran's UN envoy, Amir Saeid Iravani, said "primary investigation suggested Israel was responsible" for Saturday night's attack, which Tehran had said caused no casualties or serious damage, according to ISNA's Thursday report.
The attack came amid tension between Iran and the West over Tehran's nuclear activity and its alleged supply of arms — including long-range "suicide drones" — for Russia's aggression in Ukraine, as well as months of anti-government demonstrations at home.
"Iran reserves its legitimate and inherent right to defend its national security and firmly respond to any threat or wrongdoing of the Zionist regime (Israel) wherever and whenever it deems necessary," Iravani said in the letter.
"This action undertaken by the Zionist regime (Israel) goes against international law."
Israel has long said it is willing to strike Iranian targets if diplomacy fails to curb Tehran's nuclear or missile programmes, but does not comment on specific incidents.
READ MORE: Iran 'repels' drone attack on Isfahan military site
Talks between Iran and world powers to revive a 2015 nuclear deal have stalled since September.
Under the pact, abandoned by Washington in 2018 under then-US President Donald Trump, Tehran agreed to limit nuclear work in return for easing of sanctions.
Iran has accused Israel in the past of planning attacks using agents inside Iranian territory.
In July, Tehran said it had arrested a sabotage team of militants working for Israel who planned to blow up a "sensitive" defence industry centre in Isfahan.
"The equipment and explosives used in the Isfahan attack were transferred into Iran with the help of anti-revolutionary groups based in Iraq's Kurdistan region under orders by a foreign security service," Iran’s Nournews said on Wednesday.
Several nuclear sites are located in Isfahan province, including Natanz, the centrepiece of Iran’s uranium enrichment programme, which Iran accuses Israel of sabotaging in 2021.
There have been a number of explosions and fires around Iranian military, nuclear and industrial sites in recent years.
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