Colao has been Vodafone's Deputy CEO since September 2006. He has won respect among industry analysts for combining the crucial tasks of cutting costs at Vodafone's European operations while also increasing revenue. He has been focusing on persuading more customers to use their mobiles for data activities such as web surfing. Vodafone, which is to publish its annual results on Tuesday, declined to comment. But people familiar with the company confirmed the management changes.
Industry analysts expect Vodafone to report revenue of between 35.2 billion and 35.4 billion pounds, adjusted operating profit of 9.9 billion to 10 billion pounds, and free cash flow of five billion pounds. In 2007, Sarin was on the front foot at Vodafone, concluding the UK company's landmark purchase of a controlling stake in Hutchinson Essar, India's fourth-largest mobile operator.
The Indian deal came to symbolise Vodafone's expansion into emerging markets, as it sought to counter slowing growth at its core European operations.
That slowing European growth, highlighted by Vodafone in 2005, prompted strong criticism of Sarin by some investors who feared the company did not have a strategy to combat the problem.
At Vodafone's 2006 annual meeting, Sarin endured the spectacle of 15 per cent of investors either voting against his re-election or abstaining.
Sarin subsequently won over most investors by highlighting the growth opportunities in emerging markets and by going beyond Vodafone's mobile-centric past to sell fixed-line broadband to its European customers.
One of Colao's biggest challenges will be trying to ensure that Vodafone establishes a leading position in mobile Internet services.