Tel Aviv, Apr 12 (IANS): Israeli Prime Minister Benjamin Netanyahu said that struggling against Iran is "a huge task".

He made the remarks on Sunday hours after Iran announced that a blackout at its underground Natanz nuclear facility was an act of "nuclear terrorism", reports Xinhua news agency

"The struggle against Iran and its proxies and Iranian armament is a huge task," Netanyahu told a meeting of senior Israeli security officials, according to a statement issued by the Prime Minister's office.

"The situation that exists today is not necessarily the one that will exist tomorrow," he said.

The Hebrew-language Ynet news site quoted anonymous intelligence officials as saying Israel's Mossad espionage agency was behind the blackout.

The escalation came as US Defense Secretary Lloyd Austin arrived in Israel for a two-day visit and security talks.

The Joe Biden Biden administration has been holding indirect talks over a possible renewal of the 2015 Iran nuclear deal.

Netanyahu frequently made remarks against Iran, accusing it of planning to build nuclear weapons that will threaten Israel.