Article 131 and Article 138(1) of the Council Directive 2006/112/EC must be interpreted as precluding the tax authority of a Member State from refusing to exempt an intra-Community supply from value added tax on the sole ground that, at the time of that supply, the purchaser domiciled in the territory of the Member State of destination and who was in possession of a valid identification number for the purposes of value added tax in that Member State is neither registered in the Value Added Tax Information Exchange System nor comes under a system of taxation on intra-Community acquisitions of goods, where there is no sound evidence pointing to the existence of fraud and it is established that the basic conditions of the exemption are fulfilled. In that case, Article 138(1) of that directive, interpreted in the light of the principle of proportionality, also precludes such refusal where the vendor was aware of the circumstances of the situation of the purchaser with regard to the application of VAT and was convinced that subsequently the purchaser would be registered as an intra-Community operator with retroactive effect.