Complex sentence: In response, the heads of state decided to adopt 95% of the content of this rejected treaty and name it the Treaty of Lisbon--which was not put to the citizens for public approval except only in Ireland.
Split into simpler sentences: In response, the heads of state decided to adopt 95% of the content of the rejected treaty and name it the Treaty of Lisbon. It was not put to the citizens for public approval except in Ireland.