Pope Francis’ Encyclical Letter “Laudato Si”, published on 18 June 2015, is a moral plea for action against climate change and environmental degradation. Besides laying out the Pope’s critical stance on the ecological, spiritual and economic motives to ‘save our common home’, it also sends a central message to policy makers that: international political climate action is more important now than ever.

In Chapter Five the Pope outlines the building blocks of the “Dialogue on the Environment in the International Community”. Climate change has to be seen in the context of global interdependence. Local and regional developments linked to climate change have a global effect and entail a responsibility towards those who are and will be most affected. Hence, solutions need to be multilateral and considered from a global perspective.

 “Diplomacy”, according to the Pope, “takes on new importance in the work of developing international strategies which can anticipate serious problems affecting us all.” A determined international process built on the mutual respect of sovereignty is central to supplement action by local authorities.

This strong case for climate diplomacy can fall on fertile ground. Indeed, on  the occasion of the second European Climate Diplomacy Day - the day before the Papal Encyclical was presented - the EU’s High Representative and Vice-President Federica Mogherini made a clear statement that: tackling climate change is both a national security as well as a moral imperative.

As the pressure for a new international climate agreement to be reached at the Paris COP 21 in December is high, the Pope’s Encyclical with its strong moral rationale can assist policy makers as an added, convincing narrative in making the case for decisive and timely action.