By P.R. Venkat

U.S. private equity firm Carlyle Group Inc. plans to acquire a 25% stake in Bharti Airtel Ltd.'s data-center business, valuing it at $1.2 billion.

Entities affiliated to Carlyle will invest $235 million for the stake in Nxtra Data Ltd., a wholly owned unit of Bharti Airtel, the Indian telecommunications company said Wednesday.

Bharti Airtel will hold the remaining 75% stake.

New Delhi-based Nxtra provides data-center services to Indian and global enterprises. It has a portfolio of 10 large data centers, whose services include cloud infrastructure, managed hosting, data backup, disaster recovery and remote infrastructure management.

"The transaction is subject to the necessary regulatory approvals, including approval from the Competition Commission of India," Bharti Airtel said.

Carlyle is a global investment firm and had $217 billion of assets under management as of end-March. 



  Write to P.R. Venkat at venkat.pr@wsj.com