By Duncan Miriri

NAIROBI, Sept 17 (Reuters) - Bharti Airtel has selected IBM to manage the computing technology and services running itsnewly acquired mobile networks in 16 African countries, thecompanies said on Friday.

Bharti's chairman and chief executive, Sunila Mittal, saidthe value of the 10-year deal will be disclosed when theagreement is finalised in the fourth quarter.

"At this point in time we wouldn't like to put any value,disclose any value. We have a sense of where we are but we willannounce that at an appropriate time," the billionaire founderof Bharti told reporters in Kenya's capital.

IBM's chairman and chief executive, Samuel Palmisano, saidat the same press briefing the deal would pave the way tocheaper calling rates, thus spreading communication technologyin Africa.

"We hope to make wireless communication servicesaffordable," he said.

The two firms first entered a similar contract in India in2004, Mittal said, adding that the industry viewed the businessmodel with scepticism but growth in subscriber numbers in Indiafrom 6 million in 2004 to 141 million proved that Bharti hadmade the right decision by outsourcing to IBM.

He is replicating the model in Africa, where the purchase ofKuwait-based Zain's African business in June took Bharti's totalusers to about 190 million in 19 markets.

IBM already manages Bharti's IT infrastructure in India in a10-year deal that began in 2004. The deal had an initial valueof about $750 million, but is estimated to have grown manifoldas it is linked to Bharti's subscriber and revenue growth.

"Bharti Airtel plans to replicate the success of itsrelationship with IBM by lowering the barrier to entry for thepeople of Africa to own a mobile device," it said in astatement.

The partnership will help it scale its network and systemsto more than 100 million African customers by 2012, from about36 million now.

Kenya and Nigeria are the two largest markets for the groupin Africa. Mittal said his company will consider furtherexpansion on the continent of 1 billion people.

"We have started with a very big footprint, 16 countries insub-Saharan Africa -- it doesn't mean this will stop at that,"he said.

"Whenever an opportunity will come, we will look into thoseopportunities but we are not rushing into that at the momentbecause we have to manage our 16 countries at the moment." (Additional reporting by Devidutta Tripathy in New Delhi;Editing by Greg Mahlich)