The company signalled last month that it is reviewing its investment decisions to focus on debt reduction.
However, Ignacio Galan, chairman of Iberdrola and ScottishPower, told the group's annual investor meeting in Bilbao that its commitment to upgrade the country's distribution and transmission systems between now and 2021 and create 1500 jobs remains unchanged.
And he praised advances in the "design of Britain's energy model" which he said has provided regulatory predictability and stability.
He said: "In networks we have regulatory stability both in distribution and transmission, with tariff regimes in place until 2015 and 2021 respectively, guaranteeing sufficient and predictable remuneration for our investments that come to more than €6bn in the next few years."
ScottishPower manages the transmission network in the south of Scotland and plans to spend £2.6bn upgrading it so that it can cope with the expected increase in renewable power generation.
Mr Galan also highlighted its participation with National Grid in the building of a 260-mile undersea cable uniting Scotland and England, which is expected to be ready for operation by 2016.
While other companies, including Scottish Hydro Electric owner SSE, have been critical of plans to reform the electricity market, Mr Galan said they "represent a good opportunity for Iberdrola's generation business in the UK".
Referring to the eurozone crisis, Mr Galan claimed Iberdrola is the only major European electricity group to maintain stable profits and dividends, due to its strategy of international diversification.
He said that, provided there are no big changes in regulation, energy demand or pricing, profits for 2012 should be ahead of last year. He called on Spain, which has struggled in the eurozone crisis, to reform along free market lines.
"Spain has the opportunity to transform its economy into one that is more sustainable, competitive and deregulated," he said.
He said the country needed to revise its labour and financial laws and pursue reindustrialisation.