Suppose a country wishes to join EFTA and also join the EU Customs Union (but not the EU itself), could it do so in the long term?
I suspect that membership of both is impossible because membership of the EU Customs Union means that the EU's tariffs will apply to trade with the other EFTA members. Is this right or is there maybe another reason why or why not?
Just to pre-empt misunderstanding...
- I'm not asking about EEA or Single Market membership.
- I am only interested in long term indefinite arrangements. Temporary membership of both organisations may or may not be possible (and the possibilities might be an interesting diversion) but that's not what I'm asking about.
- A post-Brexit United Kingdom could be an example of a country that might want to join both organisations, but I'm asking for the general rule if any hypothetical country wanted to do this.