EU Moves to Become Founding Member of Special Tribunal for the Crime of Aggression Against Ukraine

The European Commission has taken a significant step toward advancing international justice by launching the process for the European Union to become a founding member of the Special Tribunal for the Crime of Aggression against Ukraine.

The proposal, adopted by the European Commission, now awaits approval by EU Member States. Once endorsed, the Commission will formally notify the EU’s intention to join the Tribunal as a founding member, positioning the European Union at the core of its governance and operations.

If confirmed, the EU will play a central institutional role, including participation in the Tribunal’s Management Committee — the body responsible for overseeing its strategic direction and functioning.

A Tribunal to Address the “Supreme International Crime”

The Special Tribunal will focus on prosecuting senior political and military leadership responsible for the crime of aggression against Ukraine — widely recognized in international law as the “mother of all crimes,” from which other atrocities flow.

The Tribunal is being established within the framework of the Council of Europe, following the agreement signed with Ukraine on 25 June 2025. This development marks a crucial milestone in closing the existing accountability gap at the highest level of leadership — an area where current international mechanisms face jurisdictional limitations.

Strong Political Backing from EU Leadership

Kaja Kallas, High Representative of the EU for Foreign Affairs and Security Policy, emphasized the broader significance of the initiative:

“Justice for the victims of aggression is the best route to lasting peace. The pursuit of justice is equally a deterrent for would-be aggressors… the right response is more accountability, not less.”

Michael McGrath, Commissioner for Democracy, Justice, the Rule of Law and Consumer Protection, underscored the moral and legal imperative:

“There can be no just peace without accountability… This is a decisive step towards establishing the Special Tribunal and ensuring that those responsible… are held to account.”

EU’s Leading Role in Building the Tribunal

The European Union has already been instrumental in shaping the Tribunal’s legal foundations. The core legal texts were politically endorsed on 9 May 2025 by a broad international coalition of states and organisations.

In addition, the EU continues to support accountability efforts through:

• the International Centre for the Prosecution of the Crime of Aggression against Ukraine (ICPA), based in The Hague

• a €10 million contribution to the Tribunal’s Advance Team, supporting its operational development

A Strategic Step Toward Justice

This move reinforces the EU’s commitment to ensuring accountability for the crime of aggression — a cornerstone of Ukraine’s Peace Formula and a prerequisite for a just and lasting peace.

For NGO Tribunal, this development represents a critical breakthrough in the global effort to establish a fully functioning Special Tribunal capable of holding top-level perpetrators accountable and restoring the integrity of international law.

Source: European Commission Press Release (March 2026)