Due to Brexit, the United Kingdom is to be considered as a non-EU Member State as of 1 January 2021. Consequently, British companies should in principle now be obliged to appoint a fiscal representative in Italy.
However, the agreement concluded between the EU and the UK on 24 December 2020 contains a clause on assistance in the recovery of VAT tax claims, which, if it has the same scope as the one concluded with Norway a few years ago, could allow British companies to be exempted from the obligation to appoint a fiscal representative in Italy.
The Italian administration has indicated that it should review the assistance clause contained in the agreement in order to determine whether or not it could allow such an exemption.
Source: Italian Ministry of economy and finances (in Italian)