Islamabad, Aug 21 (ANI): Supporters of opposition leader Imran Khan and populist cleric Tahir ul-Qadri were hopeful and determined on Thursday, after their leaders opened negotiations with the Pakistani government, in an effort to end protests against the prime minister and overcome a political impasse. The announcement on Wednesday (August 20) came the day after Pakistan_s powerful military said the two sides should engage in dialogue and warned that key government institutions were under its protection. Former cricket star Khan and cleric Tahir ul-Qadri, who controls a network of Islamic schools and hospitals, have been leading protests in the capital Islamabad since August 15. Both want Prime Minister Nawaz Sharif to resign over allegations of corruption and election rigging. Sharif, who won the last election by a landslide, has refused to step down.