PML-N leader Hamza Shahbaz on Tuesday vowed to hold Prime Minister Imran Khan to his promise of assistance in probing alleged rigging in the 2018 general election.

The PML-N leader, speaking to the media after casting his vote in the presidential election, said that his party would not let PM Khan avoid a proposed parliamentary commission's probe into allegations of rigging in the July 25 polls.

He alleged that the 2018 general election had been the most-rigged polls in the country's history and this would not be "digested".

He said that Federal Information Technology Minister Khalid Maqbool Siddiqui had described it as a "fake election", and that the former caretaker chief minister in Punjab had expressed similar views.

Hamza said that the PML-N would play its due parliamentary role to unearth the facts behind the alleged "theft of mandate".

During the first session of the 17th Punjab Assembly, Hamza Shahbaz had raised the opposition’s demand for constituting a parliamentary commission to investigate 'rigging' in July 25 elections. He raised questions over the failure of the Results Transmission System of the Election Commission of Pakistan to function as required, and alleged that "the RTS did not fail but it was manipulated to get desired results".