Plassnik said she expected that the progress in the implementation of the Croatian government's action plan for cooperation with the UN court would be properly evaluated on that occasion.
She said that as soon as it was evaluated that Croatia was cooperating fully with the Hague tribunal, European Union entry negotiations would be launched.
Plassnik was speaking to the press at Goettweig monastery, where the three-day European Forum Wachau is taking place.
The minister said Croatia's EU entry negotiations were not launched in March because there was no consensus among all Council of Ministers members.
She said chief prosecutor Carla del Ponte would submit a report to the UN Security Council on June 13, and that tomorrow the EU Task Force for Croatia would brief her about del Ponte's recent visit to Zagreb.
The Wachau forum, which began yesterday, is being attended by more than 150 participants, including the chairman of the Croatian parliamentary committee on foreign affairs, Gordan Jandrokovic.
Today participants held a plenary session called "Prospects for the Future - Europe One Year After Enlargement".
Plassnik said at the session that during its presidency of the EU in the first half of 2006, Austria would advocate supporting the European prospects of the Western Balkans countries.
We will use everything positive coming from those countries and support them. Those countries have a different pace of development in meeting all Copenhagen Criteria and standards for EU integration. We will support and bolster the quality of the process of each state, this is clear, said Plassnik.
Speaking of the situation following the recent rejection of the European Constitution in France and the Netherlands, the Austrian minister said that an analysis should be made and the right solution found through joint effort.
The European integration process can be successful if we believe each other, she said.
The European Forum Wachau, considered to be one of the most renowned international events addressing European issues, is being attended for the first time by foreign ministers Vuk Draskovic of Serbia and Montenegro and Abdullah Gul of Turkey.