By Devidutta Tripathy and Sankalp Phartiyal
MUMBAI (Reuters) - Britain's Vodafone Group and Idea Cellular agreed on Monday to merge their Indian operations in a $23 billion (18.55 billion pounds) deal, creating the country's biggest telecoms business after the entry of a new rival sparked a brutal price war.
The combined entity would have almost 400 million customers, overtaking market leader Bharti Airtel to account for about 40 percent of revenue of the world's second-biggest mobile phone services market by users after China.
The deal shows how India's mobile industry is being transformed by the launch of Reliance Jio Infocomm's 4G mobile broadband network last year.
Built at a cost of more than $20 billion by India's richest man, Mukesh Ambani, Jio has offered free services for months. That has forced India's three biggest operators - Bharti, Vodafone and Idea - to slash prices and accept lower profits, and sparked a wave of consolidation.
Vodafone, the world's second-largest cellphone operator, had previously sought to leave joint ventures it did not control but Chief Executive Vittorio Colao said the group had to be realistic in such a challenging market.
"This improves the industry structure and it also equips us and Idea to be much more competitive in the future," he told reporters. "I have no doubt that the Indian market will remain competitive but nothing can be free forever and we will be in a better position."
The two companies, which said in January that they were in talks, will have to shed spectrum in some areas to meet India's rules, although Colao said it would be "small". The deal is expected to close in 2018.
Shares in Idea rose as much as 14.3 percent after the news but then fell 10 percent to 97.70 rupees as traders said the implied deal price for Idea was well below the stock's closing price of 108.10 rupees on Friday. Vodafone shares were up 0.7 percent at 1415 GMT.
Idea said the rough deal price worked out at 72.5 rupees per share, adding that this figure was for illustrative purposes and was not the actual price.
Under the deal, Vodafone will own 45.1 percent of the merged entity, after it transfers about 4.9 percent to promoters of Idea or their affiliates for 38.74 billion rupees ($592.15 million) in cash, Idea said.
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.
The deal does not include Vodafone's 42 percent stake in Indus Towers, a joint venture between the British group, a unit of Bharti Airtel and Idea. But Vodafone and Idea said they will look to reduce their tower assets exposure, including selling their stakes in the joint venture.
Analysts have said Jio's entry is the catalyst for mergers and exits of some foreign players.
Bharti Airtel is in the process of buying Telenor's India operations, while two smaller players controlled by Malaysia's Maxis and Russia's Sistema are merging their operations with Reliance Communications' wireless unit.
"Consolidation is a much anticipated and very welcome development in this beleaguered telecom sector," said Arpita Pal Agrawal, a partner and telecom analyst at PwC India.
(Writing by Rafael Nam and Devidutta Tripathy; Additional reporting by Kate Holton in LONDON Swati Bhat in MUMBAI and Samantha Kareen Nair in BENGALURU; Editing by Muralikumar Anantharaman and Louise Heavens)