A British arms agent wanted by Indian investigators in a helicopter scam has accused the Narendra Modi government of offering Italy the freedom of two marines in exchange for evidence linking Congress chief Sonia Gandhi and her family to the corruption that hit the headlines in 2013.Christian Michel, the 54-year-old agent, has made the allegations in a letter to the International Tribunal of the Law of the Seas in Hamburg and the Permanent Court of Arbitration (PCA) at The Hague where Italy and India are battling legally over murder charges against the marines.This newspaper could not independently verify Michel's allegations."The charges are too ridiculous to comment on," foreign ministry spokesperson Vikas Swarup toldwhich shared Michel's letter with the government for its response.Till late Monday night, the Italian Prime Minister's office had not responded to an email seeking their response.But Michel told this newspaper from Dubai: "I know these are serious allegations, but I stand by them."Michel has claimed Modi made the offer at a secret "brush-by" meeting with Italian Prime Minister Matteo Renzi during the UN General Assembly in September 2015 when both leaders were in New York."At this meeting, the issue of the two marines was discussed," Michel wrote through his lawyers in his letter dated December 23, 2015. "The Indian PM proposed to the Italian PM that in return for any evidence that the key adviser to Finmeccanica/ AgustaWestland (this is a reference to myself) had any relationship to any member of the Gandhi family, the honourable PM would assist in solving the case against the two Italian marines."Neither India nor Italy has ever officially acknowledged such a "brush-by" meeting between Modi and Renzi in New York.Asked, the Indian ministry of external affairs did not deny Michel's claim of the "brush-by" meeting between Modi and Renzi, citing the presence of "so many world leaders there" to contend that a brief conversation was always possible."Brush-by" meetings are unscheduled interactions between leaders, often on the move, at times unplanned and on other occasions used to build in deniability. The two Prime Ministers are known to have spoken at least once on the telephone, on August 11, 2014, when Renzi dialled Modi asking for a "rapid, positive decision" on the marines, according to the Italian Prime Minister's office.The Italian marines are accused of shooting two Kerala fishermen dead in February 2012 and the charges against them have dragged India's relationship with Italy, once an important defence partner, to its lowest since Independence.AgustaWestland, a subsidiary of the Italian firm Finmeccanica at the time, was the firm that in 2010 won the contract to supply 12 choppers to India for Rs 3,600 crore, specifically to fly the President, Vice-President and Prime Minister at high altitudes.In 2013, Italian prosecutors accused Finmeccanica executives of paying bribes to Indian officials, including former air force chief S.P. Tyagi and his brothers, through Michel and another middleman, Ralph Haschke, to swing the deal.An Italian court acquitted the middlemen on the charge of "international corruption", but India, which began its own investigation into the case, is still pursuing the allegations.Michel, wanted by the Enforcement Directorate - which has turned to the Interpol to look for him - told this newspaper from Dubai, where he now works, that he had also written to Modi in November."I think the Prime Minister is inherently a decent man, and I wasn't - and still am not - sure if he understands fully the implications of what he is being advised, which is why I wrote to him," Michel said.In his letter to the two international courts, Michel has claimed he came to know of the meeting and conversation between Modi and Renzi through three sources in Finmeccanica while his lawyers were negotiating a settlement with the firm on outstanding claims. Michel has said in his letter that he was willing to divulge his sources to the international courts "in a confidential manner".A November 20, 2012, report in the Italian newspaper Lettera 43 had linked Michel's father Wolfgang - a businessman known to be close to the Labour Party - to the Congress."His (Michel's) contacts are stronger especially with Indian defence, that he has inherited from his father Wolfgang Max Michel Richard, a British businessman who was very active in India in the 1980s and 1990s and was close to the Congress party," the report had said. Both the Congress and Michel had denied any proximity."I have never met any member of the Gandhi family," Michel said today.Michel's allegations come at a time India and Italy are in secret talks to try and resolve political differences over the marines' case even as legal proceedings are continuing internationally.Neither nation expects the other to drop legal proceedings - the Permanent Court of Arbitration has even set a schedule through 2016 for depositions by India and Italy. But Italy wants India to allow both the marines to return to Rome - a sensitive issue politically for Renzi.One of them, Massimiliano Latorre, is already in Italy, allowed by India's Supreme Court to recuperate from a surgery to remove a brain tumour. Salvatore Girone, the other marine, is still in India, which wants a set of diplomatic and legal commitments from Italy before agreeing to his return to Rome under negotiations officials have described as a "road map".Michel's claims represent the first time anyone directly associated with either the helicopter scam or the marines' case has linked the two, apart from the Italian government's role in both. The Italian government has a 30 per cent stake in Finmeccanica.The International Tribunal of the Law of the Seas, the apex UN court on conflicts involving maritime territorial disputes, told this newspaper its work on the case was done after it ordered India to stop legal proceedings against the marines till the arbitration court reaches a verdict.Italy had approached the international tribunal last year, contending that the marines shot the fishermen in international waters - and not in Indian waters as New Delhi has insisted. "The case has now moved completely to the PCA," a tribunal spokesperson said from Hamburg. "It's no longer with us."But the PCA, which has set up a tribunal under Russian lawyer Vladimir Golitsyn, the President of the international tribunal, to hear the marines' case at The Hague, is empowered to consider Michel's letter as a valid deposition in determining its verdict.Most third-party depositions the PCA receives are from states, international organisations or non-profit groups with technical expertise in the area of dispute. If an individual petitions the court, the tribunal has one of two options, the PCA Bureau - the court's secretariat - said in an email. It can explicitly detail the possibility of individual depositions in the "rules of procedure" for the case - but it need not."Should these rules of procedure not provide for any express mechanism in this regard, it would fall to the arbitral tribunal to take a decision on the request to intervene," the PCA Bureau said.The tribunal, which takes decisions through a majority, has four arbitrators other than its chief - including one representative each nominated by India and Italy, and two lawyers picked by Golitsyn.India's nominee is P. Chandrasekhara Rao, a former secretary in the law ministry.