In a statement, Imran Khan said this is first time in the history of Pakistan that electoral fraud will be investigated.
“This becomes possible because of 126-day long protest in Islamabad”, he added.
Imran Khan held a long march from Lahore to Islamabad in August 2014, along with the charismatic cleric Tahir ul Qadri, demanding Prime Minister Nawaz Sharif resign over alleged irregularities in the 2013 elections, which his party won by a landslide.
The march turned into a sit-in demonstration in the secure red zone of the capital outside the parliament, where PTI followers camped for 126 days.
Imran Khan had vowed to stay there until the prime minister resigned, but he ended his demonstration in wake of a deadly Taliban attack on the Peshawar school in December that killed 154 people, mostly schoolchildren.
He then changed track and demanded the creation of a judicial commission to investigate the allegations of election fraud.
Chairman PTI said every single, who was involved in the election rigging must be penalized.
Pakistan Muslim League – Nawaz (PML-N) on Friday agreed to form a judicial commission to investigate alleged rigging in the 2013 general elections after months of negotiations with opposition leader Imran Khan.
Chief of Jamat-e-Islami (JI) Siraj-ul-Haq hailed formation of judicial commission by saying “this will fortify democracy and will be helpful in transforming electoral system transparent.”