JERUSALEM -- Israeli Prime Minister Benjamin Netanyahu said on Tuesday that Israel had killed Ali Larijani, secretary of Iran's Supreme National Security Council, in ongoing strikes on Iran.

Netanyahu said Israel was conducting air operations over Tehran and other Iranian cities using fighter jets and drones, adding that the campaign was creating conditions for possible "regime change" in Iran.

He also said he had spoken at length with US President Donald Trump the previous day about military cooperation.

"We will act both through indirect measures that place immense pressure on the Iranian regime and through direct actions. There are many more surprises," Netanyahu said.

The Israel Defense Forces said earlier on Tuesday that it had launched wide-scale strikes on Iranian government infrastructure in Tehran. It later said the attacks had killed Larijani and Gholamreza Soleimani, commander of Iran's Basij volunteer force.

Iran has not responded to the Israeli claims.

US-Israeli strikes on Iran entered their 18th day on Tuesday, causing heavy casualties and widespread destruction, according to Iranian authorities. Iran has retaliated with attacks that have effectively halted shipping through the Strait of Hormuz and drawn much of the region into the conflict.