ISLAMABAD, Pakistan — Prime Minister Imran Khan dissolved Pakistan’s National Assembly and called for new elections on Sunday, blocking a no-confidence vote that had been widely expected to remove him from office and plunging the country into a constitutional crisis.
The extraordinary move deepened the political turmoil that has gripped Pakistan since Mr. Khan, the international cricket star turned politician, lost the backing of the country’s powerful military and a coalition of opposition parties.
The crisis has been escalating for weeks, but its latest turn threatens to destabilize the fragile democracy in Pakistan, a nuclear-armed nation that supports the Taliban in neighboring Afghanistan and has struggled with instability and military coups since its founding 75 years ago. Still, even in a country accustomed to turmoil, Sunday’s events were stunning.
“Never in the history of Pakistan has such a thing happened,” said Ashtar Ausaf Ali, the former attorney general of Pakistan.
Opposition lawmakers lodged a petition challenging the move before the country’s Supreme Court, saying that it amounted to an “open coup against the country and the Constitution.” Allies of Mr. Khan said that the court had no authority to intervene in the Legislature’s business and repeated Mr. Khan’s recent claim that the vote is part of a U.S.-backed conspiracy to oust him.
The Supreme Court of Pakistan scheduled a hearing for Monday, setting the stage for a showdown over the country’s leadership.
Under Mr. Khan’s tenure, Pakistan has moved away from the United States, embracing a strategic partnership with China and closer ties with Russia. If he manages to remain in office, his accusations that American officials attempted to orchestrate a regime change in Pakistan will probably continue to cool the relationship between the two countries.
But the deputy speaker, Qasim Khan Suri, an ally of Mr. Khan, rejected the motion for a no-confidence vote. He said that Mr. Khan was still the prime minister and still had the power to dissolve the Assembly.
In a televised speech on Sunday, Mr. Khan confirmed that he had ordered the Legislature dissolved and doubled down on his claim that opposition parties were colluding with American officials in a conspiracy to remove him from office. Mr. Khan has offered no evidence to support his claims, and American officials have denied the allegations.
Mr. Khan called for early elections to resolve the political crisis, which members of his party have said should be held within 90 days.
“Prepare for elections,” Mr. Khan said. “No corrupt forces will decide what the future of the country will be.”
The move clearly took the opposition by surprise. Its leader, Shehbaz Sharif, held hasty meetings with his party leaders as they tried to figure out their next steps.
“It’s been a sad day in Pakistan history. Nascent democracy has been hit and damaged in a very, very brutal way,” said Mr. Sharif, who had been expected to become the interim prime minister if Mr. Khan had been removed from office.
Opposition lawmakers refused to leave the National Assembly building, apparently hoping to bring pressure on the Supreme Court to act. A handful of lawmakers from Mr. Khan’s party waved their fists as they left the building, repeatedly shouting, “Imran Khan, your supporters are countless in number.”
Ahead of the Supreme Court hearing on Monday, Chief Justice Umar Ata Bandial urged all political parties to maintain law and order until a verdict is reached — alluding to fears that Mr. Khan might whip up street agitation or even violence, as he has done in the past.
Preparing for that possibility, paramilitary troops and police officers have been deployed since Friday to effectively seal off the so-called Red Zone in Islamabad, the capital, which houses government buildings, including the parliament.
Many constitutional experts said that the country’s Supreme Court was likely to rule against the deputy speaker’s rejection of the vote of no confidence.
“The constitutional gymnastics required to make this action legal would really undermine the legitimacy of the court,” said Yasser Kureshi, a postdoctoral fellow in constitutional law at the University of Oxford.
Mr. Bandial added that several judges of the court had expressed concern about the situation after Mr. Khan dissolved the Assembly, casting doubt over the constitutionality of his move.
Still, that is no guarantee that Mr. Khan will be ousted. The longer the court takes to issue a verdict, the more time Mr. Khan’s government will have to try to weaken the opposition ahead of the next general election. Even if the court deems the ruling party’s move on Sunday as unconstitutional, it might not allow for a no-confidence vote to take place by restoring the dissolved assemblies, pushing instead for early general elections to resolve the political crisis.
The Supreme Court is also not above the fray in Pakistani politics and has often found itself embroiled in controversies.
“Our Supreme Court has a tainted past. From sanctifying military takeovers, sending political leaders to gallows or assuming executive authority clearly out of their domain,” Mustafa Nawaz Khokhar, a lawmaker with the opposition Pakistan Peoples Party, said in a tweet.
Some analysts in Pakistan speculated that, as the crisis drags on, Mr. Khan might have members of the opposition arrested, on the grounds that they were part of what he claims to be an American conspiracy to remove him from office. Mr. Khan has led a growing crackdown on dissent, and opponents have accused him of targeting opposition members under the pretext of an anticorruption campaign.
Standing outside the parliament’s chamber, one lawmaker from Mr. Khan’s Tehreek-e-Insaf party, Kanwal Shauzab, said that arresting opposition members was a “possibility” as long as it was done “in accordance with the law of the land.”
“We are not going to go after the opposition without any reason. It’s what they have done. They have to pay for their own deeds,” she added.
Such arrests could reduce the majority that had seemed poised to oust Mr. Khan. But his move Sunday seemed to risk costing him supporters of his own. One outspoken lawmaker from his party, Aamir Liaquat Husain, resigned in protest, joining dozens of members of Mr. Khan’s coalition who have defected in recent weeks.
Trying to head off such defections, the interior minister said Tehreek-e-Insaf had the support of Pakistan’s institutions in dissolving the Legislature — an apparent reference to the military, whose backing is considered critical to the survival of Pakistan’s civilian governments.
The military had appeared to withdraw support from Mr. Khan late last year after a dispute over its leadership and longstanding differences in the country’s foreign policy and security agenda. Military leaders, who have expressed interest in deepening Pakistan’s ties with the United States, have maintained that the military remains neutral in the current political crisis.
But a spokesman for the army denied that it had been involved in or supported Sunday’s developments. It was the first time military leaders had so openly suggested that they did not support Mr. Khan’s bid to stay in office. To some, it raised the possibility of military intervention — a familiar pattern in Pakistan’s history — should the political crisis drag on.
“Historically, the longer such a constitutional deadlock carries on,” Mr. Kureshi said, “the greater chances of some kind of military intervention.”
Christina Goldbaum and Salman Masood reported from Islamabad, Pakistan. Zia ur-Rehman contributed reporting from Karachi, Pakistan.