ISLAMABAD - Prime Minister Shehbaz Sharif Monday lashed out at Pakistan Tehreek-e-Insaf (PTI) Chairman Imran Khan for playing ‘vicious role’ to harm Pakistan’s external relations. “Niazi’s interview with FT in which he rebutted his foreign conspiracy theory is a reminder of vicious role he played to harm Pakistan’s external relations while pursuing his own petty politics. Nation is shocked by his deceit & treachery inflicting irreparable damage on Pakistan,” the premier tweeted late Monday. PM Shehbaz Sharif returned home on Monday after concluding his private visit to London. The prime minister reached London on Wednesday after attending the Climate Implementation Summit in Sharm Al Sheikh, Egypt. During his stay in London, PM Shehbaz held meetings with Pakistan Muslim League-Nawaz (PML-N) leader Nawaz Sharif and discussed various important issues.