The son of the last shah toppled in Iran's 1979 Islamic revolution said Thursday that whoever the clerical government chooses to succeed the late Ayatollah Ali Khamenei will be illegitimate.

Reza Pahlavi, who has positioned himself as an alternative if the Islamic republic falls, said on social media that "victory is near" after Khamenei was killed last weekend as Mideast war began.

"Any attempt to appoint a successor for him is pre-destined to fail. Whomever is introduced... will lack legitimacy and will be considered an accomplice to the bloody record of this regime and its criminal leaders," Pahlavi said.

Mojtaba Khamenei, the son of Khamenei, is among the leading contenders to succeed his father.