We have not been pressured by any institution, said Election Commission of Pakistan Secretary Babar Yaqoob.
Speaking to the media in Islamabad on Saturday, he said that ballot papers have been printed and distributed across the country and the last papers will be sent to Karachi today (July 21).
He said CCTV cameras will be installed at polling stations before July 25.
The police and army will be responsible for security at polling stations, he said, adding that 800,000 security personnel will be on duty during the election.
Yaqoob also promised that postal ballots will be scrutinsed properly.
All parties are campaigning for the elections and are being given equal opportunities, he claimed.