Croatia's Rejected Z4 Plan for Serbian Autonomy

The Z4 plan, drafted in 1994 by diplomats from the United States, Russia, the United Nations and the European Union, proposed to turn Croatia into a confederation by creating two autonomous regions – Kotar Knin and Kotar Glina – for the self‑declared Republic of Serbian Krajina. The proposal would have given those regions their own legislature, government, courts, police, a separate currency and dual Croatian‑Yugoslav citizenship, while leaving defence, foreign affairs and finance to the Croatian state.

Croatian President Franjo Tuđman and Serbian Krajina leader Mile Martić rejected the plan as unacceptable. Tuđman called it a threat to Croatia’s sovereignty, and Martić publicly dismissed it as “nonsense”. The plan never progressed beyond negotiations and was abandoned after the 1995 Operation Oluja.