A three-judge bench headed by Chief Justice Iftikhar Chaudhry disqualified Gilani in response to several petitions that had challenged National Assembly Speaker Fehmida Mirza's decision not to disqualify the premier following his conviction of contempt.
The bench ruled that the post of premier had been vacant since April 26, when another seven-judge bench had convicted Gilani of contempt for refusing to reopen graft cases in Switzerland against President Asif Ali Zardari.
The bench had also directed the Election Commission to issue a notification regarding Gilani's disqualification.
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