Islamabad, Jan 30 (Al Jazeera) - A Pakistan court has sentenced former Prime Minister Imran Khan and his close aide, former Foreign Minister Shah Mahmood Qureshi, to 10 years in jail in a case related to the leaking of state secrets.

The special court set up in a prison in Rawalpindi on Tuesday announced the sentence in the so-called cypher case, which pertains to a diplomatic cable that Khan claims proves his allegation that his removal from power in 2022 was a conspiracy.

The court established under the Official Secrets Act found Khan guilty of misusing the confidential cable sent by a former Pakistani ambassador to the United States.

Khan has repeatedly denied the charge, saying the document contained evidence that his removal as prime minister was a plot hatched by his political opponents and the powerful military, with help from the US administration. Washington and the Pakistani army reject the accusation.

Khan was Pakistan’s premier from August 2018 to April 2022 when he lost a vote of confidence in the parliament. He has been in jail since August last year, facing trial in multiple cases.

The sentencing against the country’s main opposition leader comes about a week before the general elections, scheduled on February 8.

Syed Zulfiqar Bukhari, a spokesperson for Khan’s Pakistan Tehreek-e-Insaf (PTI) party, told Al Jazeera the PTI will challenge the court’s decision.

“This was pretty much a writing on the wall,” he said, adding that the trial was held in an “unlawful manner”.

“Our lawyers were not allowed to represent Imran Khan. They were not even allowed to cross-examine the witnesses. What was unfolding in the court was merely a charade and a sham,” Bukhari said.

It is Khan’s second conviction in less than a year. In August, he was sentenced to three years in a corruption case, which barred him from contesting the national elections.

The vote follows a massive crackdown against the PTI, which saw dozens of its leaders quitting the party and thousands of its members and supporters jailed.

Recently, the party also lost its election symbol – a cricket bat – and had been forced to field its candidates as independents.

But Bukhari said the verdict against Khan and Qureshi will only work in favour of the beleaguered party.

“With the sentence coming at a time when elections are less than 10 days away, it will only motivate our supporters and help them come out in droves. It looks like the authorities want to suppress the PTI and its voter base, but their acts will only drive us to vote in bigger numbers,” he told Al Jazeera.