Prime Minister Anthony Albanese of Australia accused Iran on Tuesday of orchestrating two arson attacks on Jewish institutions in Australia last year and said he was severing diplomatic ties with Iran and expelling its diplomats.

“These were extraordinary and dangerous acts of aggression orchestrated by a foreign nation on Australian soil,” Mr. Albanese said at a news conference, where he was flanked by the country’s top intelligence official, its foreign minister and its home affairs minister.

Mr. Albanese said security agencies believed Iran had been behind the arson attacks on Lewis’ Continental Kitchen in Sydney in October and the Adass synagogue in Melbourne two months later. No one was injured in the attacks.

Mike Burgess, Australia’s head of intelligence, said an investigation stretching across several months uncovered links between the attacks and Iran’s Islamic Revolutionary Guards Corps, which Australia said it would list as a terrorist organization.

This is a developing story.