In early 1992 the war spread to neighboring Bosnia and Herzegovina, where the Croatian government helped arm the Croatian Defence Council (HVO), the main Croat army, and the Bosniak Army of the Republic of Bosnia and Herzegovina (ARBiH). The Defence Ministry established logistics centers for sending men, weapons and ammunition to the ARBiH. HV units were deployed in Bosnian Posavina and participated in Operation Jackal against the VRS. On 18 November 1991 the Croatian Community of Herzeg-Bosnia was established as an autonomous Croat territorial unit. Šušak was one of the chief supporters of Herzeg-Bosnia in the government and according to historian Marko Attila Hoare acted as a "conduit" of Croatian support for Bosnian Croat separatism. Relations between Croats and Bosniaks worsened by the end of 1992, resulting in the Croat–Bosniak War. During the war, HV units were deployed on the frontlines against the VRS in eastern Herzegovina. Volunteers with origins from Herzeg-Bosnia were sent by the Defence Ministry to the HVO, the official military formation of Herzeg-Bosnia. At its peak the amount of money from Croatia that funded the HVO surpassed $500,000 per day. Šušak supported the Vance-Owen plan that would establish 10 ethnically based provinces in Bosnia and Herzegovina. He worked closely with EC representative David Owen, who adopted some of his proposals. On 18 March 1994 the US-brokered Washington Agreement was signed that ended the Croat–Bosniak conflict and created the Croat-Bosniak Federation.