I have a European passport issued in Estonia and ID card. In my passport the nationality stated as Belarusian, as I was born there, but I have been living in Estonia for more than 30 years.
I am going to visit UK and I've checked the requirements online, my ticket says I have to go for a passport/visa checked/stamp. The airline booking form included
country of issued passport fields, so I entered them as in my passport:
Belarusian (nationality) and
Estonia (country) correspondingly.
I was sure I do not need visa to visit UK as I'm EU passport holder and Estonian citizen which is in EEA.