Complex sentence: Lyana Armstrong-Emery is a Gibraltarian politician, and the current party leader of the Gibraltar Reform Party, a left-of-centre decentralist party with a close association with the Green Party of England and Wales, and the Cornish Mebyon Kernow.
Split into simpler sentences: Lyana Armstrong-Emery is the current party leader of the Gibraltar Reform Party. This party is a left-of-centre decentralist Gibraltarian party with a close association with the Green Party of England and Wales, and the Cornish Mebyon Kernow.