Pakistan Tehreek-i-Insaf (PTI) Chairman Imran Khan, addressing a rally in Lahore on Friday in the run-up to the NA-120 by-poll, urged voters in the constituency to use their vote to show the Supreme Court that it rejects "criminals".

The PTI, whose Yasmin Rashid is competing in the by-poll, is embroiled in a tussle with the PML-N over the constituency vacated by ousted premier Nawaz Sharif.

The PML-N nominated Sharif's wife, Begum Kulsoom, as its candidate for the seat after the Supreme Court (SC) disqualified the former prime minister for being 'dishonest' in a landmark ruling on the Panama Papers case.

The former premier's daughter Maryam Nawaz is campaigning for the upcoming by-poll on behalf of Begum Kulsoom who is undergoing cancer treatment in London.

"Are you going to vote for the person who was given a year by the Supreme Court to prove innocence, and was also given an opportunity by the joint investigation team, but could not answer questions about the money trail [for his assets]?" Khan asked the gathering at Qurtaba Chowk.

"The crimes committed by small thieves are nothing compared to the damage caused by these big thieves," he told his audience.

"With your vote, you will tell the Supreme Court that you are grateful this day has come, that the most powerful thief [in the country] was disqualified."

"With your vote, you will tell the Supreme Court that you want criminals to be sent to jail," he asserted.

"Your vote will strengthen the court and send the message that you want these groups in the country to be jailed, to prevent them from representing you in assemblies and becoming ministers," he said.

"The powerful in Pakistan can do anything illegal while the weak cannot even practice their rights without bribing officials," Khan claimed.

"If Pakistan has not been able to reach its destiny in the world, it is because petty thieves are found in jails, whereas the big thieves are escorted around by the police," he said.

"Your vote will strengthen the court... It will decide the direction of Pakistan," he maintained.

"This is the time to change the country's direction," Khan said, claiming that "a new era will begin on September 17" ─ the date of the scheduled by-poll.

The PTI chairman wondered how Sharif's children had been able to earn billions of rupees from business "within a period of five to six years", whereas he had, only after a 13-year cricketing career, been able to afford a flat in London.

"When the PML-N come to ask you for votes, ask them what business did Nawaz's children that allowed them to became billionaires? Ask [Finance Minister Ishaq] Dar's children what business did they do to become billionaires?"

"Maryam Nawaz should give lessons on how to become a billionaire in a short amount of time," he said.

The PTI chief congratulated Yasmin Rashid on what he implied was her imminent victory in the election.

"I am saying this not because your [Rashid's] competition is easy ─ it is difficult. Your competition is against the federal government, the administration and the police, the way they are helping Maryam Nawaz, [they can] do it all but Lahore has decided."

"Through their vote, they will tell people 'We are standing with the judiciary and with justice,'" he said.