"Through this crime, the Zionist regime has laid the foundation for a bitter and painful fate and it will definitely get it," says Khamenei in a statement on X.
Ayatollah says that Israel with "its satanic, blood-stained hands" attacked Iran.
He confirms reports that high-ranking Iranian military personnel and nuclear technology researchers were killed in Israel's attacks.
"If God wills, their successors and colleagues will continue their work without delay."
Israel can "count on a harsh punishment," according to Khamenei.
