Gojko Susak has died," Prime Minister Zlatko Matesa told an emergency government session carried live on state television. "Susak, who won all battles and whose dream of an independent Croatia came true, lost the only battle -- that against the evil disease --- last night," he added before the government stood for a minute's silence. Susak, who was 53, will be buried on Thursday in Zagreb's Mirogoj cemetery. The government declared the day a national day of mourning. He had been suffering from lung cancer and was said by diplomats to have had one lung removed in a U.S. military hospital last August. Susak was seen as an undisputed authority over the hardline Bosnian Croat lobby within the Croatian government, representing their interests in Zagreb and for a long time was the second most powerful man in the country. The son of Croat emigres from the Herzegovina region of Bosnia, Susak came to Croatia from Canada in 1990 to help promote and fund President Franjo Tudjman's successful election campaign and further the dream of independence. He raised millions of dollars from the wealthy right-wing Croat diaspora which also helped to fund the build-up of Croatia's army before it triumphantly recaptured most of the Serb-held areas of the country in 1995. In two sweeping offensives Croatia reclaimed all its occupied territory. Some 180,000 Serbs are estimated to have fled the advance in western Croatia. He was Tudjman's closest adviser during the war and made few conciliatory gestures or tokens towards the 600,000 Serbs living in Croatia before Yugoslavia broke up in 1990. He was reported to have fired missiles, together with other members of the ruling Croatian Democratic Union, into a Serb village in April 1991, an event which caused no casualties but fanned the flames of war among Serbs.