Aditya Birla Group, the majority owner of Idea, will own 26 percent while other shareholders will own the remaining 28.9 percent. Aditya Birla and Vodafone eventually aim to own an equal share of the joint venture, with a combined enterprise value of $23.2 billion.

Vodafone, which will cut its net debt by about $8.2 billion with the deal, has endured a tumultuous ride since it entered India in 2007, with a high-profile tax battle and a long-delayed Indian listing. The South Asian country contributes more than 10 percent of its revenues.

Colao said on Friday the pending case, with India demanding more than $2 billion in taxes, will not affect the deal, which needs regulatory approval.

Investors have welcomed Vodafone’s move to address its most difficult market, with the deal enabling the British company to reduce leverage and gain additional financial flexibility which could help it to invest more in Europe.

“This looks like a good deal for Vodafone shareholders based on hugely sensible strategic logic, which values Vodafone India at a premium to our valuation, and opens the door to significantly greater synergies than we had anticipated,” analysts at Berenberg said.