Court of Justice: principle of proportionality must be preserved when assurance of naturalisation is revoked and applicant loses EU citizenship 

Today, the Court of Justice ruled in Wiener Landesregierung (Révocation d’une assurance de naturalisation) (C-118/20) that Member States must have due regard to the principle of proportionality when revoking the assurance of granting their nationality when such revocation results in a permanent loss of the applicant’s EU citizenship.

In 2014, the then competent Austrian administrative authority assured an Estonian national, JY, that she would be granted Austrian nationality if she could prove that she had relinquished her Estonian nationality. Consequently, she relinquished her Estonian nationality and has been stateless since. In 2017, however, the newly competent Austrian administrative authority revoked the assurance of natural