ISLAMABAD: Pakistan Muslim League-Nawaz (PML-N) President and former prime minister Mohammad Nawaz Sharif on Saturday underscored the need of national unity in addressing the multifaceted challenges facing Pakistan. He was talking to Senator Irfan Siddiqui, parliamentary party leader in the Senate. Nawaz Sharif expressed grave concern over elements working to destabilise the country and tarnish its image. He argued that …