The Taoiseach Enda Kenny's among almost 150 world leaders gathering in Paris for talks on climate change.
The UN wants them to agree to big cuts in emissions to limit the rise in global temperature.
Yesterday campaigners staged demonstrations in cities across the world.
Nearly 200 are being held after clashes with police in Paris.
Sky's Enda Brady is in the French capital, and says after the terror attacks there, security's incredibly tight.