LONDON (Reuters) - The chief executive of Europe's biggest mobile group Vodafone <VOD.L> warned that Britain needs to remain in the European Union to influence the development of the single market for digital services, one the fastest growing parts of the economy.

"We think the digital single market is the next big opportunity for the economy, in Europe in general and for Britain in particular," Vittorio Colao, chief executive of the British company, told BBC radio on Tuesday.

Colao said Britain was a leader in digital goods and services, and could help set in agenda in areas such as e-commerce and cyber security.

"It would be a great missed opportunity if Britain was trying to sit outside of it and not shaping it from inside," he said.

(Reporting by Paul Sandle, editing by Louise Heavens)