The Irish Republic’s main electricity company ESB is in talks to buy Northern Ireland Electricity.
The proposed takeover was announced to the Dublin and London stock exchanges.
NIE is the transmission and distribution business of Viridian, Northern Ireland’s main power company. It is ultimately owned by Arcapita, a Bahrain-based bank, which bought Viridian for more than £1.6bn four years ago.
The Northern Ireland Utility Regulator will be keeping tabs on the deal and said it would “exercise our regulatory role to protect the interests of Northern Ireland consumers”.
ESB already operates the Coolkeeragh power plant near Londonderry in Northern Ireland. It is also buying the power generated by the SeaGen tidal turbine in Strangford Lough.
NIE is the largest business within Viridian, which also owns the Huntstown generation plant in Dublin.