47It will also be for the referring court, when reviewing whether there has been compliance with the principle of proportionality, to determine whether the prohibition on leaving the country is appropriate to ensure the achievement of the objective it pursues and does not go beyond what is necessary to attain it (see, to that effect, Jipa, paragraph 29). In that respect, even if the impossibility of recovering the debt at issue were to constitute a genuine, present and sufficiently serious threat affecting one of the fundamental interests of society, it will be for the referring court to determine, inter alia, whether, by depriving Mr Aladzhov of the possibility of pursuing part of his professional activity abroad and thereby depriving him of part of his income, the measure of prohibition at issue is both appropriate to ensure the recovery of the tax sought and necessary for that purpose. It will be also be for the referring court to determine that there were no other measures other than that of a prohibition on leaving the territory which would have been equally effective to obtain that recovery, but would not have encroached on freedom of movement.