Iran's parliament voted on Wednesday in favour of taking Mahmoud Ahmadinejad to court over what lawmakers said is a violation of the countrys constitution stemming from the presidents move last month to declare himself caretaker oil minister. The vote in the conservative-dominated assembly is its latest action against Ahmadinejad since the president in April publicly challenged Irans highest authority,Supreme Leader Ayatollah Ali Khamenei. That challenge was triggered by Ahmadinejads attempt to sack the powerful intelligence minister,Heidar Moslehi,a move Khamenei blocked. Although Ahmadinejad publicly backed down in the confrontation with Khamenei weeks later,it emboldened his hard-line rivals in parliament. And last month,Ahmadinejad incurred the wrath of the Guardian Council,Irans constitutional watchdog body,when he sacked Oil Minister Masoud Mirkazemi and declared himself caretaker oil minister. The confrontations appear to be part of a power struggle ahead of parliamentary elections next year and the vote for Ahmadinejads successor in mid-2013.