Do UK ministers really know what will happen as a consequence of a UK exit from the European Union? The Europe minister, David Lidington, seems to think that he does know. Or does he? In a Daily Telegraph report today, Lidington was quoted as saying: "Everything we take for granted about access to the single market - trade taking place without customs checks or paperwork at national frontiers, the right of British citizens to go and live in Spain or France - those would all be up in the air. It is massive. It is massive what is at risk."

Eurosceptic ministers say that such comments are all part of scaremongering tactics by David Cameron and his allies for the "remain" vote. But Lidington's observation that Brexit would stop UK citizens being able to move abroad is bound to spread anxiety, not to say renewed demands by all UK citizens currently in EU countries to have their right to vote in the referendum. If these citizens' rights at present are being jeopardised, then it is only morally right that they should all be able to participate. Their choice to live abroad will, in most cases, have been taken based on the freedom of movement within the single market.

There again, not everyone living in Spain or elsewhere made the move because of the single market. There were those who had done so prior to the single market. Yes, the rules were different then, and yes, the rules will doubtless be different if there is a leave vote, but to suggest that UK citizens would be prevented from moving (or living) abroad does indeed sound like scaremongering. The negotiation of an alternative relationship with Brussels that would be the immediate consequence of a leave vote would surely include retention of rights on movement. These apply to citizens of certain non-EU countries as it is, while The Telegraph itself has pointed out that the Vienna Convention on the Law of Treaties (1969) contains articles based on "acquired rights", which individuals attain and hold despite changes to treaties (such as those pertaining to the EU).

Those already resident would, by implication of this, retain their rights. Those wishing to move would be more affected, but if other non-EU countries can have rights of movement, why should it not be the same for UK citizens?