Pakistan's main opposition leader reiterated Monday a call for the transfer of presidential powers to the prime minister and parliament, highlighting an issue that could bring political turmoil. Assassinated former prime minister Benazir Bhutto and Nawaz Sharif had in 2006 agreed on a Charter of Democracy aimed at transferring powers back to the prime minister and restoring a parliamentary system. Sharif called again Monday for the full implementation of the charter in talks with Prime Minister Yousaf Raza Gilani. “We want the Charter of Democracy to be immediately implemented ... the 17th amendment should immediately be repealed,” Sharif said referring to an amendment introduced by former president Pervez Musharraf giving the president power to dissolve parliament. “The parliament should be sovereign and there should be an independent judiciary,” he told reporters with Gilani after their talks in the city of Lahore. President Asif Ali Zardari, Bhutto's widower and leader of her party, has promised to implement the charter and transfer powers back to the prime minister. But critics say he is reluctant to turn himself into a ceremonial leader and has been dragging his feet. Gilani said a parliamentary committee was working on reforms and he promised good news on the charter. Sharif can mobilize supporters for big protests, especially in the politically most important province of Punjab, which could plunge the country into crisis. While some party members have raised the possibility of a street campaign if the reforms are not introduced, Sharif issued no such ultimatum Monday.