Pakistan's top court dismissed the prime minister for contempt on Tuesday, ushering in a new round of political turmoil in a nation vital to American hopes of withdrawing from Afghanistan.

The Supreme Court ruling was a major escalation in a long-running confrontation between the judges and the government, and appeared to be a knockout blow against Prime Minister Yousuf Reza Gilani, effectively dismissing his Cabinet as well.

A spokesman for Gilani's Pakistan People's Party, Zaman Kaira, acknowledged that Gilani "was no longer prime minister" but didn't say what the government would do now.

Gilani and his party, the largest in the ruling coalition, held an emergency meeting to discuss the ruling.

In the past, the party has said it would have the numbers in parliament to elect a new premier if Gilani was ousted by the court. Some suggested that Gilani and his boss, President Asif Ali Zardari, might try to resist the order. That could spark institutional deadlock and social unrest, even raising the possibility of the army staging a coup as it has done three times in the country's past.

The political chaos comes amid a near breakdown in relations between the United States and Pakistan, whose ties to the Afghan Taliban make it important in any negotiated settlement in neighboring Afghanistan. Washington wants Pakistan to reopen supply lines to Afghanistan that were blocked in November to protest U.S. airstrikes that killed 24 Pakistani border troops. The latest upheaval makes a speedy resolution more unlikely.

The Supreme Court ordered the country's election commission to formally dismiss Gilani and said he had not legally been the prime minister since April 26, when the court convicted him for contempt for refusing to open a corruption probe against Zardari dating back to the 1990s and involving the jurisdiction of courts in Switzerland.

"The office of the prime minister shall be deemed to be vacant accordingly," said Chief Justice Iftikhar Chaudry, who then ordered Zardari to begin the process of electing a new premier.

The ruling was the culmination of a process that began in a Supreme Court decision in 2009 ordering the government to ask authorities in Switzerland to reopen the cases against Zardari. Gilani refused, saying the president had immunity from prosecution so long as he was in office, and in January the court ordered contempt proceedings against him.

Gilani has been refusing to step down, saying he has done nothing wrong and accusing the Supreme Court's chief justice of having a vendetta against him and his party. It was unclear whether the government could appeal the court decision.

Fawad Chaudhry, an adviser to the prime minister, said Gilani would continue working as premier and any final decision about his fate would be taken by the parliament. He did not elaborate. Continued...