On 25 April 2019, the Irish and French regulatory authorities adopted a joint decision to finance the Celtic Interconnector, the first electrical link between Ireland and continental Europe.

CRU and CRE have agreed on a cost allocation that reflects the benefits provided by this interconnection to the two countries, leading France to pay 35% of the investment costs for this project. Both regulators affirm the need for strong financial support from the European Union and support the grant application of the Irish and French grid operators, Eirgrid and Electricity Transmission Network (RTE).

The Celtic project will be the first interconnection between the two countries, linking Knockraha in Ireland to La Martyre in France. With a capacity of 700 MW, this project represents an investment of € 930 million and should be commissioned in 2026.

Celtic has been declared a Common Interest Project by the European Commission since 2013. As such, it is eligible for financial support from the European Union. In the context of the UK's exit from the European Union, the Celtic project will establish a direct link between Ireland and the European internal energy market. It will also contribute to the energy transition and bring many positive benefits in terms of security of supply, market integration and sustainability for both host countries and the European Union as a whole. CRU and CRE support the application of the Celtic project for a European grant covering at least 60% of the project's investment costs (including a minimum of € 195 million for France).