In the context of electricity, a transmission cable that transfers electricity across borders. It enables electricity to be generated in one market and used (or traded) in another. Great Britain has sub-sea electricity interconnectors with Ireland and other European countries. Ofgem grants electricity interconnector licences. For more information, see Practice notes, Electricity interconnectors: overview and EU network codes for electricity: overview.

In the context of gas, a gas pipeline that transfers gas across borders. Great Britain has sub-sea gas interconnectors with Ireland, Belgium and Holland. Ofgem grants gas interconnector licences. For more information, see Practice note, EU network codes for gas: overview.