The House of Commons Library published a Briefing Paper on 19 January 2017 exploring the potential impact of Brexit on those currently exercising free movement rights.
In 2015 (according to the most recent available data) there were around 1.2 million British citizens living in other EU countries, compared with around 3.2 million EU citizens living in the UK.
Ahead of the negotiations, all we currently know (which is not very much) is that the Government has expressed an intention to protect the status of EU nationals already living here. It was said on 13 January 2017 in response to a written question that “the only circumstances in which that would not be possible is if British citizens’ rights in European member states were not protected”.
It seems reasonable to assume that the negotiations will result in the same protection for EU nationals in the UK and vice versa. The big question concerns what level of protection will be retained. Under EU law, EU citizens who reside legally for a continuous period of five years in another EU Member State automatically acquire the right to permanent residence there. The UK could choose to offer permanent residence pursuant to domestic law to all those who have already acquired permanent residence in the UK under EU law.
A potentially more difficult question concerns those who have resided in the UK for under five years. Will additional conditions or procedures be imposed on the right to permanent residence for these people? In what circumstances will the UK be able to strip EU nationals of their right to permanent residence? The same questions apply to UK citizens abroad.