Iran's supreme leader Ayatollah Ali Khamenei on Monday formally endorsed hardliner Mahmoud Ahmadinejad as president for a new four-year term amid intense political turmoil in the Islamic republic.

But in a sign of the escalating feud between rival political factions over Ahmadinejad's hotly disputed re-election, opposition leaders were absent from the ceremony, state-owned Al-Alam television said.