The regulators for The Netherlands, Belgium and GB have asked ECA to model their respective markets to assess whether the interconnectors, IUK and BBL, have potential market power and whether they are capable of exercising it by restricting gas volumes transferred between GB and Belgium or The Netherlands in order to move gas prices in either market; the value of interconnectors to their shipper customers is based on the differences in prices between the markets they serve, which is known as congestion rents.