Employers already need to carry out right to work checks on EU citizens, as they do with all prospective employees to prevent illegal working. The statutory code of practice and published guidance for employers are clear that EU citizens can evidence their right to work by showing a passport or national identity card, and employers should continue to refer to these documents.
EU nationals may also use Home Office residence documentation as evidence of their right to work, but they are not currently required to do so. Even in the unlikely event of a no deal situation, this position will not change next March. We will publish a White Paper on the future immigration system later in the autumn.