The family of Prime Minister Nawaz Sharif was defiant Monday, defending their ownership of offshore companies after they were named in the Panama Papers, one of the biggest leaks in history.The leak, comprising 11.5 million documents from Panama-based law firm Mossack Fonseca, shows how some of the world's most powerful people have secreted away their money in offshore jurisdictions.Among those named are three of Sharif's four children -- Maryam, who has been tipped to be his political successor; Hasan and Hussain, with the records showing they owned London real estate through offshore companies administrated by the firm."Nawaz Sharif does not own any company but having companies in the name of his children also raises questions," Umar Cheema of the independent Center for Investigative Reporting in Pakistan (CIRP) told AFP.The CIRP is partnered with the Investigative Consortium of Independent Journalists (ICIJ), which spent months poring over the documents ahead of Sunday's online release."There are more than 200 Pakistanis which our report has identified, and they include lawyers, lawmakers and some people from the judiciary," he said.Opposition leader Imran Khan issued a swift call for action against Sharif after the release."Our stance vindicated again as Sharif's wealth stashed abroad exposed," he tweeted, adding the country's accountability watchdog, tax authorities and election commission "must take action".But Sharif's son Hussain told a private broadcaster that his family had done "nothing wrong"."Those apartments are ours and those offshore companies are also ours," he said in comments aired by the channel Monday."There is nothing wrong with it and I have never concealed them, nor do I need to do that."It is according to British law and laws of other countries that it is a legal way to avoid unnecessary tax via offshore companies."He left Pakistan in 1992, he added, and therefore is not resident, adding Pakistani tax law "says that if you are not staying in Pakistan for more than 138 days, then you are not required to declare your assets".Regarding Imran's call for the National Accountability Bureau (NAB) to investigate, he said "we voluntarily present ourselves before it or any other judicial and investigative institution in Pakistan".And he issued one final dig at Imran, calling on him to provide "proof that the Prime Minister has not declared his assets"."If he is successful in that then we are ready to accept our fault and undergo punishment," he said.Nawaz Sharif's office has not yet responded to requests for comment by AFP.Ali Nadir, a financial analyst, said the use of offshore companies was in many cases legitimate.But, he added: "I believe political and business leaders will be hard pressed to take the privacy defence given the worldwide move towards a better track of money, tax evasion, laundering and corruption."This may also start more locally focused probes as there are likely to be disclosure issues."The Panama Papers have whipped a storm of controversy over off-shore wealth, ensnaring political leaders, sports figures and underworld members across the globe in a snowballing scandal.Information Minister Pervaiz Rashid denied any wrongdoing on the Sharifs' part."Every man has the right to do what he wants with his assets, to throw them in the sea, to sell them, or to establish a trust for them. There is no crime in this in Pakistani law or in international law," he said.Responding to Pakistan Tehreek-e-Insaf (PTI) chairman Imran Khan’s remarks against Prime Minister Nawaz Sharif and his family’s alleged illegal assets in foreign accounts, Information Minister Pervez Rashid brushed aside “allegations without any proofs”.“Nawaz Sharif regularly pays his taxes and has no funds abroad,” the information minister said while speaking to mediamen in Islamabad on Monday.Rashid said Imran’s accusations have once again proven false, advising the cricketer-turned-politician to apologise for hurling false accusations against political personalities without having any proofs.“Panama leaks did not talk about any company of Sharif family which is enough proof that all the allegations of stashing funds abroad against the family are false,” he maintained.The minister further said that the Sharif family was forced out of the country in late 90s and were not allowed to come back to Pakistan for a long time which “compelled them to establish their business abroad.”“Sons of Nawaz Sharif have been living abroad for a long time and they were not allowed to come to Pakistan which is why they started their business abroad.”“Today, no one talks about the mistreatment which was meted out to the business of Sharif family during the past regimes in the country,” he lamented.“Even Nawaz Sharif’s deadliest woes could not prove a single corruption case against him. Benazir Bhutto never hurled any accusation against Nawaz Sharif for corruption nor could Musharraf prove anything against him.”