Centrica chair: Referendum pledge means 'period of uncertainty' for businesses

Sir Roger Carr, chairman of British Gas owners Centrica, told Richard Edgar that David Cameron's "positive tone" on Europe was welcomed by the business community but that the prospect of a referendum means a "period of uncertainty."

He said businesses and politicians must prove that there is a "real, positive purpose in being in Europe that is good for the United Kingdom."

He added that Europe is "the largest single market we have" and "for us, it is about 50 percent of our exports."

"That kind of access, unfettered, is critically important to the long term while we build up other markets in parallel."