ISLAMABAD, JUNE 6: The Nawaz Sharif Government was today severely rapped by the opposition for the imposition of emergency in the country in the wake of nuclear tests by India and Pakistan.The main opposition, Pakistan People's Party (PPP), expressed its serious reservations over the intentions of the government by imposing emergency while raising the bogey of external aggression during a joint session of the parliament to approve the proclamation of emergency.PPP leader Aitzaz Ahsan, who led his party during the joint session in the absence of leader of opposition, Benazir Bhutto, described the imposition of emergency as a ``colossal tragedy'' while drawing a parallel with India.``India also carried out nuclear tests, did they also impose emergency in their country and took away the fundamental rights of their citizens'', Aitzaz said.Aitzaz, who launched scathing attacks on Prime Minister Nawaz Sharif, said that the Prime Minister has failed to take the nation along as ``he imposed the emergencyon a nation which gave its whole-hearted support to him for the nuclear tests''.While pointing out contradictions in Sharif's statement, Aitzaz said that at one stage the Prime Minister was boasting of establishing parity with India by carrying out the nuclear tests and removing threat against Pakistan but on the other hand he justified imposition of emergency because of threat from external aggression.As Aitzaz continued firing salvos on the Prime Minister, Sharif suddenly rose from his seat and walked out of the House which prompted the opposition leader to quip, ``I am dismayed (at Prime Minister walking out) but not surprised''.Earlier Safdar Abbasi, another PPP leader, while displaying the presidential proclamation for imposition of emergency, drew the attention of the house that it clearly mentioned emergency is being imposed due to threat from external aggression and asked the treasury benches from where this threat had come.The opposition also charged the government of ignoring the rulesand procedures for convening the joint session of parliament for the approval of presidential proclamation and alleged that the government was trying to ``bulldoze'' the approval using its overwhelming majority in the house.The opposition also staged a two-minute walk out from the house in protest when Speaker Ilahi Baksh Soomro, overruled their objections and their request for reconvening the joint sitting after three days for discussing the approval of emergency.The joint session finally approved the impostion of emergency.