Gojko Susak, the hard-line Croatian defence minister and closest ally of President Franjo Tudjman, has died aged 53. A tough nationalist who devoted his life to creating and preserving Croatia's independence, he also became a useful ally of the United States as it sought to end the Bosnian war.

As defence minister from 1991, Susak led Croatia's fight against the Serb rebellion that temporarily left a third of Croatia in Serb hands before the 1995 Croatian offensive that defeated the rebels.

A native of the Croat-dominated region of Herzegovina in south-west Bosnia, he favoured close ties between Bosnian Croats and Croatia proper. He moved away from the idea of annexing territories inhabited by Bosnian Croats because of pressure from the United States and its allies.

Susak was born on March 16, 1945, in Siroki Brijeg, Bosnia-Herzegovina. In 1969, he broke off studies of mathematics and physics and went to Canada, eventually running a Toronto pizzeria. In 1989, as the communist Yugoslavia he despised was disintegrating, Susak returned, helping Tudjman win Croatia's first multi-party elections in 1990.

Croatia declared independence on June 25, 1991. Susak earned respect among many Croats for organising and arming - through ties to wealthy emigres - a force that defended most territory against rebel Serbs and the Serb-led Yugoslav People's Army during a six-month war. With American help, Susak modernised his army, and it crushed the Serb rebels in two lightning offensives in 1995.

Susak's methods came under some criticism. The company he formed, RH Alan, was rumoured to have acquired weapons in violation of a UN arms embargo. Critics and some former soldiers claimed Susak condoned 1991 and 1995 atrocities against Serbs. He spearheaded support to Bosnia's Croats throughout the 1992-95 war there, including a year-long conflict with the Muslims, during which both sides committed atrocities.

Susak helped to persuade Bosnia's Croats to accept the 1995 Dayton peace accord, which thwarted the extremists' goal of uniting with Croatia proper. In 1997, fearing Washington would punish an unco-operative Croatia, Susak helped arrange the surrender of 11 Bosnian Croat war crimes suspects to The Hague tribunal.

He is survived by wife Djurdja. They had no children.