Electricidade de Portugal, the national power utility, plans to raise €1.2bn ($1.47bn) in Portugal's biggest rights issue to date to finance the group's expansion in Spain ahead of the launch of a single Iberian energy market.

The operation is also aimed at reassuring investors that the former state-owned monopoly is now an independent private-sector company entirely free of government influence, said João Talone, EdP chairman, in an interview.