Khan has appealed to Pakistan's Supreme Court to probe the rigging allegations and proposed the name of retired Supreme Court judge Justice Nasir Aslam Zahid to head the commission.
Khan said the commission should complete investigations within one month.
"We will call off the protest if the allegations are not proven. But if they are, we want resignation of the Prime Minister (Nawaz Sharif)," the chairman of Pakistan Tehreek-i-Insaf said while addressing his supporters.
In August, Sharif had requested the Supreme Court to set up a three-member judicial commission to probe allegations of rigging of polls. The apex court, till date, has not taken any action.
Following the anti-government protests, Tehreek-i-Insaf and PML-N held talks to determine the terms for the proposed judicial commission but couldn't evolve a consensus.
Pressure is mounting on Khan to call of protests. But he is adamant and has asked workers to prepare for massive protest in the capital on November 30, if no decision comes out.