Pakistan Tehreek-i-Insaf (PTI), the political party of jailed former Pakistani prime minister Imran Khan, announced on Monday that it will join with the Sunni Ittehad Council party (SIC) in a bid to form a government.

PTI-backed independents were the biggest winner in the February elections but they were forbidden to run under the party’s banner and they did not win enough seats to claim an outright majority. The second- and third-place finishers, the Pakistan Muslim League (PMLN) and Pakistan People’s Party (PPP) said last week they would assemble a seven-party coalition to claim the seats they need to form a government, most likely installing incumbent PMLN Prime Minister Shehbaz Sharif as its leader.

Such a move would probably enrage Khan’s supporters, who believe that established forces engaged in vote fraud to keep PTI from winning a majority of seats and forming a government without coalition allies. Khan, who was jailed and banned from politics on corruption and national security charges, called on his supporters to stage a ballot-box revolution against the corrupt Pakistani political establishment.

PTI’s showing in the election was remarkable, given that the party was effectively banned from ballots and its leader appears likely to spend the rest of his life in prison. Khan’s supporters, who rioted in cities across the country when he was arrested in May, will not take much consolation in knowing they were only able to thwart the political comeback of former PM Nawaz Sharif, who said last week he would step aside in favor of his younger brother.

PTI interim leader Barrister Gohar Khan said on Monday the 100 independent winners aligned with his party would join forces with SIC to put together the necessary 133 seats in the National Assembly to form a government. The SIC confirmed it signed a memorandum of understanding with PTI and the coalition would take its orders from the imprisoned Imran Khan.

Gohar explained that teaming up with the SIC would enable the alliance to claim a proportional total of “reserved seats” in the National Assembly to reach the total it needs. Under Pakistani law, 70 seats in the national parliament are reserved for female and non-Muslim candidates, and those seats can only be held by members of a political party.

SIC leader Hafiz Hamid Raza said his party has been on good terms with PTI for many years and was happy to correct what it saw as a grave injustice when a court barred PTI from using its cricket-bat logo on ballots. Party logos are crucial because Pakistan has a large portion of illiterate rural voters.

“We have been their ally for the last 8 years and supported each other as we did now by providing our platform so that the PTI can get their share in reserved seats,” Raza said.

“I want to clarify one more thing, that our support of Imran Khan and the PTI is unconditional and without any demand. I want to make it clear, in black and white, that the policy will be of the PTI and Imran Khan sahib,” Raza added.

The SIC is an alliance of small Islamist parties that was formed about 15 years ago. PTI originally vowed that it would not dilute its ideological strength by forming a coalition with any other party but, when it became clear it could not claim enough seats to form a government on its own, it began negotiating with a few parties that shared Khan’s hardline Islamist views. 

A deal that seemed to be taking shape with a party called the Majlis Wahdat-i-Muslimeen (MWM) fell apart over the weekend. One of the major sticking points was apparently PTI’s insistence that any party joined by its slate of nominal independents must be completely loyal to Imran Khan.

The PTI-SIC alliance may still lack the votes it needs to overcome Shehbaz Sharif and his PMLN-PPP coalition, but predictions were clouded on Saturday when a senior Pakistani election official admitted vote-rigging took place in the city of Rawalpindi.

The official, Liaqat Ali Chatha, said he would resign his post and surrender himself to the police.

“We converted losers into winners, reversing margins of 70,000 votes of independent candidates for 13 national Parliament seats,” Chatha said at a news conference on Saturday. He was talking about shifting votes away from PTI’s slate of independent candidates.

Chatha said he came clean because he was losing sleep over “stabbing the country in its back” by conspiring with other officials to rig the election. PTI leaders called on other officials to step forward and admit their own guilt. Pakistan’s election commission denied Chatha’s accusations but promised to investigate credible accusations of vote rigging.