Mobile phone giant Vodafone’s new boss has revealed plans to slash 11,000 jobs across the group over the next three years as she said the firm “must change” to address its poor performance. Margherita Della Valle, recently appointed Vodafone’s group chief executive, said the cull comes as part of a plan to simplify the business. It will impact the group’s UK headquarters in Newbury, Berkshire, as well as markets worldwide.