The law firm at the centre of the Panama Papers saga reportedly faces a writ from a US hedge fund that successfully sued Argentina.

Paul Singer's Elliott Management Corp has accused Mossack Fonseca of helping Argentine clients hide money as Elliott was pursuing the Argentine government to pay off defaulted bonds. Agence France-Presse, the news agency, says that a legal brief it has seen, filed in a Nevada court in late May, focuses on Mossack Fonseca's business of setting up anonymously-owned companies and trusts for clients who often want to hide funds offshore from tax and legal officials.

The lawsuit says that while it was pursuing its claims against Argentina in 2014, Elliott's unit NML Capital sought help in identifying and tracing assets linked to some shell companies registered in Nevada. It said that Mossack Fonseca, though having evident close links to "MF Nevada" - a corporate services provider linked to those shell companies - insisted in the court that the two only had very limited ties. For that reason, Mossack Fonseca insisted it could not provide the data that NML wanted.

A report in May, also by AFP, stated that Mossack Fonseca is suing a journalists’ group for leaking data it says is false. The law firm is issuing a writ against the International Consortium of Investigative Journalists. The ICIJ has put a searchable database of 11½ million documents about more than 200,000 offshore companies onto its website, all gleaned from the law firm's database by 'John Doe,' a shadowy American who says that he wants to help US prosecutors catch money-launderers. The Washington DC-based organisation first revealed that it had obtained the leaked, or stolen, data in April.

The Panama Papers saga has seen the downfall of Icelandic prime minister Sigmundur David Gunnlaugsson, and, ironically, a senior Chilean figure in Transparency International. The papers also purportedly show that Australian premier Malcolm Turnbull had a firm based in the British Virgin Islands that Mossack Fonseca created for him. British premier David Cameron’s late father also had an account at one stage that was based in Panama.

The affair has reignited debate about the proper distinction to be drawn between legitimate client privacy and secrecy, as well as the issue of whether beneficial owners of trusts and other structures should be publicly disclosed.