Venice Commission
The Venice Commission declared that the referendum was illegal under both Ukrainian and Crimean Constitutions, and violated international standards and norms. The Venice Commission stressed that self-determination was to be understood primarily as internal self-determination within the framework of the existing borders and not as external self-determination through secession. Moreover, the Venice Commission opined, any referendum on the status of a territory should have been preceded by serious negotiations among all stakeholders, and that such negotiations did not take place.