The EU has said it is ready to bring forward membership talks with Croatia on the condition that it hands over indicted war crimes suspects.
Croatian Prime Minister Ivo Sanader says he is willing to co-operate
A statement adopted by EU leaders at a Brussels summit said talks could start in March, if it co-operates with the war crimes court in The Hague.
Friday's announcement means talks should start a month ahead of schedule.
Romania and Bulgaria were invited to sign entry treaties in April, ahead of their planned entry in January 2007.
But their entry could still be delayed by one year if they fail to make further progress on judicial reform, fighting corruption, strengthening border controls and cutting state aid to industry, says the BBC's Oana Lungescu in Brussels.
The issue of war crimes suspects is one of the sticking points for Croatia.
The chief prosecutor at the UN war crimes tribunal in The Hague, Carla Del Ponte went to the United Nations last month to repeat her complaint that Croatia and other states were not doing enough to find suspects wanted for crimes committed during the wars in the Balkans in the 1990s.
Gen Ante Gotovina: Accused of war crimes against ethnic Serbs
On Thursday, Croatian Prime Minister Ivo Sanader told EU leaders he was fully committed to handing over the main Croatian suspect, General Ante Gotovina.
Gen Gotovina is accused of ordering the killing of more than 100 ethnic Serbs and expelling 150,000 more during an offensive in 1995 to recapture Croatian lands seized by Serb forces.
European Commission President Jose Manuel Barroso described close co-operation with the court as the necessary condition to any progress towards European integration.
Meanwhile, 15 Roma children have filed racial discrimination claims against Croatia at Europe's human rights court.
Two human rights organisations representing the children, from northern Croatia, say the children have been racially segregated from other pupils and have suffered severe educational and psychological harm.
The case was formally lodged with the European Court of Human Rights in Strasbourg on Wednesday.
Earlier this year, a Croatian court ruled that Roma children could be educated separately if they did not speak Croatian fluently enough to attend mainstream classes.