The former cricket star had moved to break up the lower chamber ahead of a no-confidence vote against him that he had looked destined to lose.
The court said in its judgment that the vote should now go ahead.
“The advice tendered by the Prime Minister on or about 03.04.2022 to the President to dissolve the Assembly was contrary to the Constitution and of no legal effect,” Chief Justice of Pakistan Umar Ata Bandial stated, as he read out a 13-point order to a packed courtroom.
Dozens of opposition members outside the imposing white stone building shouted in jubilation when the unanimous ruling was announced. Angry Khan supporters chanted anti-American slogans in reply as police in riot gear separated the sides.
The constitutional crisis has threatened economic and social stability in the nuclear-armed nation of 220 million people, with the rupee currency hitting all-time lows earlier on Thursday and foreign exchange reserves tumbling.
When opposition parties united against Khan last week to push for the no-confidence motion, the deputy speaker of parliament, a member of Khan’s party, threw out the motion, ruling it was part of a foreign conspiracy and unconstitutional.
Khan then dissolved parliament.
Thursday’s ruling in the capital Islamabad could spell the premature end of Khan’s tenure in a country where no elected leader has finished their full term in office.
The 69-year-old, who steered Pakistan to cricket World Cup victory in 1992, came to power in 2018 after rallying the country behind his vision of a corruption-free, prosperous nation respected on the world stage.
But it appears that the firebrand nationalist’s fame and charisma may not be enough to keep him in power. He could not deliver on all of his lofty promises and failed to avert an economic decline partly sparked by the COVID-19 pandemic.
If Khan were to lose the no-confidence vote, the opposition could nominate its own prime minister and hold power until August 2023, by which date fresh elections have to be held.
The opposition has already said it wants early elections, but only after delivering a political defeat to Khan and passing legislation it says is required to ensure the next polls are free and fair.
Pakistan’s election commission said on Thursday that the earliest it could hold the ballot was October.
Economic policymakers will want to see the crisis resolved as quickly as possible. Pakistan is in the middle of an International Monetary Fund bailout which it desperately needs to shore up hard currency reserves which are perilously low.
The Pakistan rupee took a battering on Thursday as the country awaited the court’s judgment, hitting record lows.
“As (the) dollar continues to soar, a massive economic meltdown is staring the country in the face,” Shehbaz Sherif, an opposition leader who is among the favourites to replace Khan as prime minister, said in a tweet.
The crisis also threatens Pakistan’s relationship with long-time ally the United States, who Khan has blamed for being behind a conspiracy to overthrow him. Washington denies this.
Some political analysts said the country’s powerful military viewed Khan and his conservative agenda favourably when he won a general election, but that generals’ support has since waned. Khan has denied enjoying their backing.
The military has stepped in to remove civilian governments and take over on three occasions since Pakistan’s independence in 1947, citing the need to end political uncertainty.
The current military leadership says it is not involved in politics or in the current situation