India's mobile operators added 11.59 million subscribers in May, taking the country's total to 415.25 million, according to the latest figures from Telecom Regulatory Authority of India (TRAI) .

The number of new line activations was down slightly on April's 11.9 million. (See India Tops 400M Mobile Subs.)

While May's additions represent yet another amazing month of growth for the developing market's wireless players, government-owned Bharat Sanchar Nigam Ltd. (BSNL) suffered a poor month in the mobile arena, adding just 424,291 new connections. That's less than half of the number BSNL added in April and accounts for less than 4 percent of the total additions in May. BSNL's share of the May additions is way down on its overall market share of close to 13 percent, and marks a sharp decline in fortunes. (See table below.)

Table 1: India's Mobile Operator Rankings for May 2009

BSNL's subscriber numbers actually fell in eight "circles" (service areas), with Rajasthan registering the operator's biggest loss, more than 50,000. The other six operators active in this circle all posted gains, including new entrant Sistema Shyam TeleServices Ltd. , which added 98,663 new connections.

BSNL's downturn isn't just due to competition, as its numbers also fell in two areas where BSNL is the only operator. It lost a handful of subscribers in both rural Chhatisgarh, which sits in the Madhya Pradesh circle, and Himalayan Uttaranchal, which is in Uttar Pradesh (West). (For more on India's telecom circles, see A Guide to India's Telecom Market.)

It's not surprising, therefore, that pressure is increasing for BSNL to become more commercially orientated, something that could be achieved through an IPO or an investment from an overseas partner. The latter option is now being viewed more favorably than an IPO, according to this report from India's Economic Times.

Of the private operators that compete with BSNL, Bharti Airtel Ltd. (Mumbai: BHARTIARTL) added the most new mobile connections last month, and, with 99,549,208 lines activated at the end of May, will now have surpassed the landmark of 100 million mobile connections.

Vodafone India also boosted its customer base significantly and was the second-biggest mover in May, securing just short of 22 percent of the monthly additions, compared to its 18 percent share of the total market. It also accounted for more connections than Reliance Communications Ltd. , closing the gap on the country's No. 2 mobile operator.Vodafone Essar's impressive growth looks set to continue as Nokia Networks has now completed the extension of the operator's network in seven circles -- Assam, Bihar, Himachal Pradesh, Jammu & Kashmir, Madhya Pradesh, North East, and Orissa -– ahead of further network capacity enhancement activities throughout this year and into 2010. (See NSN Completes V'fone Essar Build.)

Overall (including fixed lines), India now has 452.9 million comm services lines and a teledensity of 38.88. Broadband connections continue to grow steadily, with another 120,000 added to the subscriber base in May, taking the total number of lines with a downstream speed of more than 256 Kbit/s to 6.4 million, while the number of fixed telephony subscribers fell again, down 150,000 to 37.66 million.

— Catherine Haslam, Asia Editor, Light Reading