Pakistan's Imran Khan and Tahirul Qadri call for PM to resign
17 August 2014 Last updated at 02:11 BST
Thousands of protesters gathered in Pakistan's capital Islamabad as rally leaders Imran Khan and Tahirul Qadri called for Prime Minister Nawaz Sharif to step down.
They are alleging rigging in the 2013 elections, which saw the first civilian government transfer of power.
Imran Khan and cleric Tahirul Qadri, who have separate groups of supporters, have vowed to together bring one million followers on to the streets of the city.
Nichola Carroll reports.