Islamabad, Pakistan (CNN) -- Pakistan's president has summoned the lower house of parliament to meet Friday to elect a new prime minister after the nation's top court ruled that Yousuf Raza Gilani is ineligible to hold office.
The session is set to convene early Friday, said Mehboob Gurmaini, a parliament spokesman.
President Asif Ali Zardari postponed a trip to Russia to huddle with senior members of his Pakistan Peoples Party to nominate a candidate.
Pakistan state television reported Makhdoom Shahabuddin, a longtime member of parliament who has served in several administrations, was selected. The candidate served as Gilani's textile minister.
Shadabuddin is considered a Zardari loyalist likely to adhere to the party agenda if elected.
The Supreme Court declared Gilani disqualified retroactive to April 26, the day he was convicted of contempt charges stemming from his refusal to call on Swiss authorities to reopen old corruption charges against Zardari.
"Since no appeal was filed against this judgment, the conviction has attained finality," said the ruling, read in the court by Chief Justice Iftikhar Muhammad Chaudhry.
"He has also ceased to be the prime minister of Pakistan with effect from the said date (April 26), and office of the prime minister shall be deemed to be vacant accordingly."
The speaker of Pakistan's National Assembly had 30 days from the day of the April verdict to ask the Election Commission to pursue disqualification proceedings if she viewed Gilani's conviction as cause for dismissal.
In a five-page decision released last month, Speaker Fahmida Mirza said she did not believe the prime minister's refusal to follow the Supreme Court's order justified disqualification. The speaker's ruling seemed to give a boost to the prime minister, who decided not to appeal the court's conviction.
The Supreme Court essentially overruled the speaker's decision Tuesday. The commission issued a "notification of disqualification" of Gilani after the order.
"The president of Pakistan is required to take necessary steps under the constitution to ensure continuation of the democratic process through the parliamentary system of government in the country," the Supreme Court order said.
Hours after the court issued its ruling, Gilani had vacated the sprawling prime minister's residence in Islamabad with his political future in doubt.
Federal Information Minister Qamar Zaman Kaira said senior party members have decided that Zardari, who is the party chairman, will make a final decision on how to proceed after he meets with coalition partners. A presidential pardon has not yet been discussed.
Supporters of Gilani and the party say the court's ruling was politically motivated because of bad blood between the Supreme Court's popular Chief Justice Iftikhar Chaudhry and Zardari.
Pakistan has been beset by militant activity and political tumult for years.
Fighters from the Taliban and al Qaeda use the northwestern territories as bases for attacks in Afghanistan, and U.S. drones regularly strike militant positions. The United States and the Afghan government have been concerned that the warfare and instability could hurt the government.
But the crisis and a possible departure of the prime minister wouldn't have a seismic effect on the nation's stability and political system because the country's civilian government is dominated by the Pakistan Peoples Party.
A new prime minister would simply take the place of Gilani as a representative of the party. The current government is approaching the end of its term in February, the first time since Pakistan's independence in 1947 that an administration would complete a five-year term.
CNN's Reza Sayah and journalist Nasir Habib contributed to this report.