The Chairman and CEO of Spanish energy company Iberdrola, which owns Scottish Power, has criticized U.K. opposition leader Ed Miliband for threatening to freeze energy bills for consumers for 20 months.
Ignacio Galan told CNBC in Brussels that Britain desperately needed new investments in the energy sector because of a lack of investments in the last 10 years. Instead, he said, Miliband's focus on consumer power bills showed he didn't understand rising input costs for energy companies.
(Read More: Energy leaders warn of blackouts across Europe)
"I'd be delighted if Mr Miliband can already fix a cap for the international gas prices, for the international oil prices, for the international coal prices, we'll be delighted to be able to do so," Galan said. "But I feel that he does not have enough knowledge and power to fix this cap as well for those raw materials, which are already creating this energy."
Galan said that if badly needed investments weren't made, Britain could see some blackouts this winter or in the next two winters.
"To create some uncertainty around this, is absolutely very negative," he added.
Miliband was unavailable for comment when contacted by CNBC.
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