Litvinenko inquest: newspapers launch challenge over withholding of evidence Alexander Litvinenko pictured shortly before his death in 2006. Photograph: Natasja Weitsz/Getty Images Media groups will on Tuesday challenge what they describe as a "deeply troubling" attempt by the government to withhold evidence from the inquest into the murder of Alexander Litvinenko. The Guardian, the BBC, the Financial Times and other newspapers are challenging a submission by the foreign secretary, William Hague, to conceal sensitive documents. Hague argues the material could harm "national security," as well as the UK's "international relations." The government has refused to say what evidence it wants to hide. But it is likely to deal with revelations made at a hearing in December that at the time of his poisoning in November 2006 Litvinenko was actively working for the British secret services. Litvinenko was also a "paid agent" of the Spanish security services. MI6 encouraged him to supply information to the Spanish about Russian mafia activities, and alleged links between top organised criminals and the Kremlin, the hearing was told. Litvinenko travelled to Spain in 2006 and met his MI6 handler, "Martin," shortly before his fateful encounter with Andrei Lugovoi and Dmitry Kovtun, the two men accused of killing him. The inquest - scheduled to begin in May - will hear claims that the pair were part of a "Russian state" plot to murder Litvinenko using radioactive polonium. The fact that Litvinenko - a former Russian spy - was working for MI6 raises embarrassing questions as to whether British intelligence should have done more to protect him. Litvinenko had a dedicated phone to contact "Martin" and received regular payments to his bank account from MI6 and Madrid, it emerged in December. In making their submission to the coroner, Sir Robert Owen, on Tuesday, the media groups will seek to argue that Hague's attempt to withhold evidence could undermine public confidence in the inquest. Currently the media - as well as Litvinenko's widow, Marina, and son, Anatoly, - are "completely in the dark" over what material the FCO seeks to exclude. The media groups will seek to persuade the coroner that the government has also failed to explain what "harm" the release of the information might cause. Nor has it properly considered "lesser measures," such as redaction, which would allow some disclosure of sensitive documents, or the possibility of closed sessions. Alex Bailin QC, the lawyer acting for the Guardian, will argue that "the public and media are faced with a situation where a public inquest into a death ... may have large amounts of highly relevant evidence excluded from consideration by the inquest. Such a prospect is deeply troubling. There are grave public concerns that allegations of "state-sponsored assassination" on the streets of London require "maximum openness." Additionally, the inquest is likely to be the only judicial forum where evidence will be heard, since the Kremlin has refused to extradite Lugovoi and Kovtun. Speaking on Monday, Litvinenko's friend Alex Goldfarb said the foreign secretary appeared unwilling to offend Russia's "vindictive" president. Goldfarb told the Guardian: "I recognise that Mr Hague has a well-founded interest not to rock the boat with [Vladimir] Putin. He's afraid. He's afraid Putin will not vote the way he wants in the UN or squeeze Britain's interests. He added: "The inquest is a balance between the interests of international relations and justice. The bottom line is how far do you compromise with your own justice and decency, and the benefits from doing business with arrogant, murderous and dictatorial foreign states? Goldfarb said forensic evidence and reports from Scotland Yard had already been disclosed to interested parties. But he said he was worried the government wanted to keep secret highly sensitive documents showing links between Russian mobsters in Spain and "Putin's inner circle." "That's what Sasha [Litvinenko] was up to," Goldfarb said. An FCO spokesperson said: "The government has made an application to the court for public interest immunity in line with its duty to protect national security and the coroner is responsible for deciding that application based on the overall public interest." Owen is due to hear submissions from the media at a hearing in the Royal Courts of Justice on Tuesday. He has previously indicated that he wants the inquest to be as open and broad as possible.