Iran's atomic energy agency said Wednesday that a potential Israeli attack on nuclear facilities "will not succeed" or "cause any serious damage", predicting that such an attack was "unlikely" to happen.
The remarks come as the region braces for Israel's retaliation after Iran launched at the start of the month about 200 missiles at Israel in its second ever direct attack on its arch-foe.
"It is very unlikely to happen," said agency spokesman Behrouz Kamalvandi in a video interview with the Nournews agency.
"In the event of an attack on a key site: be sure it will not succeed," he said.
"And if they (Israel) do such a stupid thing, it is very unlikely that they will cause serious damage to us and even if we assume that they can cause some damage, the country can quickly compensate for it," he added.
Tehran said its October 1 attack on Israel was in retaliation for the killing of Iran-aligned militant leaders in the region and a general in its Revolutionary Guards.
The missile barrage came after an Israeli air raid killed Hezbollah chief Hassan Nasrallah and Revolutionary Guards general Abbas Nilforoushan in Beirut on September 27.
It also followed the killing of the political leader of Palestinian militant group Hamas, Ismail Haniyeh, on July 31 in Tehran in an attack widely blamed on Israel.
Israel has since vowed to retaliate, with Defence Minister Yoav Gallant saying Israel's response will be "deadly, precise and surprising".
US President Joe Biden, whose government is Israel's top arms supplier, has warned Israel against striking Iran's nuclear or oil facilities.
The office of Israeli Prime Minister Benjamin Netanyahu said that Israel -- and not its top ally the United States -- would decide how to strike back.
"We listen to the opinions of the United States, but we will make our final decisions based on our national interest," it said Tuesday.
Iran has warned that any attack on its "infrastructure" would provoke an "even stronger response", while Revolutionary Guards general Rassul Sanairad said an attack on nuclear or energy sites would cross a red line.
Iran's Foreign Minister Abbas Araghchi on Tuesday warned UN chief Antonio Guterres that Tehran is ready for a "decisive and regretful" response if Israel attacks.