ps On my current European Union passport my nationality is stamped as 'British Citizen.'

The wording inside the old British 10yr passport states..

'Her Brittanic majesty's Principal Secretary of Statefor foreign and commonwealth affairs requests and requiresin the name of her Majestyall those whom it may concern to allow the bearer to pass freely without let or hindrance and to afford the bearer such assistance and protection as maybe necessary.'

In the new euro passport they have dropped the 'principal' and 'for foreign and commonwealth affairs.'