Israel Atomic Energy Commission Director-General Zeev Snir on Tuesday said that the security surrounding Israel's nuclear research sites has been "improved and reinforced."
The move, Snir said during a meeting of the International Atomic Energy Agency (IAEA), is due to Iran's threats to attack the research sites.
"We cannot ignore the repeated and explicit threats, made by Iran and its proxies, to attack Israel's nuclear sites," he said.
"These outrageous threats, require Israel to take action and continue to protect and defend its nuclear facilities. These facilities are constantly upgraded and reinforced, in line with IAEA safety guidelines, in order to withstand any attack."
Iran has consistently threatened to annihilate Israel, and recently demanded the United Nations force Israel to sign the non-proliferation treaty and supervise its nuclear activities.
Iran itself in 2015 signed an agreement in 2015 under which sanctions against Iran were lifted in exchange for the country curbing its nuclear weapons program.
However, in April Israeli Prime Minister Binyamin Netanyahu revealed that Iran had lied, covering up the continuation of its nuclear weapons program. In August, Iranian Foreign Minister Mohammad Javad Zarif explicitly said that honoring the 2015 is "not Iran's only option."