Europe ‘a la carte’: The whats and whys behind UK opt-outs
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“The UK and Irish opt-out to the Lisbon Treaty are nothing new,” explains Camino Mortera, research fellow at the Centre for European Reform.
“The EU project is based on the idea of differentiated integration or 'variable-geometry', by which the EU project is based on the idea that integration can be done at different levels and speeds, due to the irreconcilable differences between member states,” she said.