International lawyers have “laid the foundations” for a special tribunal to try Russia for the crime of aggression, the EU has said, hailing a significant step towards holding Vladimir Putin and his top officials accountable for the invasion of Ukraine.

In a statement late on Tuesday, the EU executive declared a breakthrough that it said would mean the Russian political and military leaders “who bear the greatest responsibility” would be held to account.

The tribunal’s creation was initially proposed by Ukraine just days after the full-scale invasion, but for nearly three years lawyers have wrangled over finding the right courtroom.