- Speaker rules no-confidence vote was part of foreign conspiracy
- Country's cabinet, national assembly dissolved on PM's orders
- Fresh polls sought in 90 days but legal battles to decide matter
Pakistan's political turmoil deepened on Sunday, when Prime Minister Imran Khan avoided an attempt to oust him and sought fresh elections after dissolving parliament, a move the opposition called treasonous and vowed to fight.
The deputy speaker of parliament, a member of Khan's party, blocked an opposition no-confidence motion that Khan had widely been expected to lose, ruling it was part of a foreign conspiracy and unconstitutional.
That stymied the opposition's attempt to come to power, and set up a potential legal showdown over the Constitution in the country of 220 million people.
Opposition leader Shehbaz Sharif called the blocking of the vote "nothing short of high treason" and said on Twitter there would be consequences for "blatant & brazen violation of the Constitution." He added he hoped the Supreme Court would uphold the Constitution.
Bilawal Bhutto Zardari, head of the opposition Pakistan People's Party, promised a sit-in at parliament and told reporters, "We are also moving to the Supreme Court today."
The Supreme Court's chief justice said on Sunday evening the court would hear the matter on Monday and that any directions given by the president and prime minister would be subject to the court's orders.
The opposition blames Khan for failing to revive the economy and crack down on corruption. Khan has said, without showing evidence, that the move to oust him was orchestrated by the United States, a claim Washington denies.
Khan said later on Sunday his evidence of the conspiracy was accepted by the National Security Committee.
"When the country's highest national security body confirms this, then the [parliamentary] proceedings were irrelevant, the numbers were irrelevant," Khan said.
US officials on Sunday denied any involvement.
"There is no truth to these allegations," a State Department spokesperson told Reuters on Sunday, adding "we respect and support Pakistan's constitutional process and the rule of law."
The opposition and analysts say Khan, an international cricket champion turned politician who rose to power in 2018 on the military's support, had fallen out with it, a charge he and the military deny.
"Army has nothing to do with the political process," Major General Babar Iftikhar, the head of the military's public relations wing, said when asked about any involvement in Sunday's events.
No prime minister has finished a full five-year term since Pakistan's independence from Britain in 1947, and generals on several occasions have ruled the country, which is perennially at odds with fellow nuclear-armed neighbour India.
President Arif Alvi, also of Khan's party, approved the prime minister's request to dissolve parliament and cabinet. Khan will remain prime minister, said Fawad Chaudhry, the former minister of information and law.
Farrukh Habib, another former minister, said fresh elections would be held in 90 days, although that decision rests with the president and the election commission.
Deputy Attorney General Raja Khalid, a top prosecutor, resigned, calling the government's dissolving of parliament unconstitutional. "What has happened can only be expected in the rule of a dictator," he told local media.
The political fight comes as Pakistan faces high inflation, dwindling foreign reserves and widening deficits. The country is in a tough International Monetary Fund bailout programme.
Islamabad also faces international pressure to prod the Taliban in neighbouring Afghanistan to meet human rights commitments while trying to limit instability there.
Khan lost his majority in parliament after allies quit his coalition government and he suffered a spate of defections within his Pakistan Tehreek-e-Insaf party.
A prominent newspaper had recently said Khan was "as good as gone", but he had urged his supporters to take to the streets on Sunday ahead of the planned vote.
On the streets of the capital Islamabad, there was a heavy police and paramilitary presence, with shipping containers used to block off roads, according to a Reuters witness.
Police were seen detaining three supporters of Khan's ruling Pakistan Tehreek-e-Insaf party outside parliament, but the streets were otherwise calm.