The late chief of the International Atomic Energy Agency (IAEA) Yukiya Amano was assassinated in a covert, joint operation by Israel and the U.S., a report distributed Wednesday by the semi-official Iran Tasnim news agency claims.

Tasnim alleged Amano is thought to have been “eliminated” by the two countries “so the UN nuclear agency could have a new chief.”

No evidence was provided to back the spectacular claim.

The late Japanese secretary general of the IAEA was reportedly standing against the U.S. and Israeli “heavy pressures to open a false case against Iran on the nuclear issue,” the Tasnim sources said.

The Iranian sources also said that the U.S. and Israel “had kept the news of death of Amano in the dark for a couple of days after his funeral.”

Amano, the Japanese diplomat who led the UN nuclear agency for a decade, died on July 18.

Having led the agency since 2009, the former Japanese diplomat oversaw various major events including cleanup of the 2011 Fukushima nuclear disaster and negotiations over Iran’s nuclear weapons program.

“The Secretariat of the International Atomic Energy Agency regrets to inform with the deepest sadness of the passing away of Director General Yukiya Amano,” the IAEA said in a statement.

Amano’s death came before the end of his term, due to run until November 2021. He was planning to step down after becoming increasingly frail following an unspecified medical procedure last September, as Breitbart News reported.

The agency also revealed he was preparing to send a letter to the board of governors explaining his decision retire, part of which was released to the public.