MOSCOW, Dec 23 - Rostelecom (ROS.N), Russia's largest long-distance fixed-line call operator, is to buy a significant stake in IT company NVision Group to diversify its business in the face of stiff competition from mobile phones.

This deal fits with the strategy of the company, which is directed at further diversification of the business and will enable Rostelecom to strengthen its positions in new market segments, chief executive Anton Kolpakov said on Wednesday.

Rostelecom (RTKM.MM), which on Tuesday reported a 72.5 percent slump in 9-month profit to $107 million, did not disclose the size of its future NVision stake but said the deal should close in the second quarter of 2010. [ID:nLDE5BH0CI]

Unnamed sources told the Kommersant newspaper it would be a 25 percent holding costing around $60 million. Rostelecom will also get an option to increase its holding in NVision to 100 percent, the business daily reported.

NVision, whose services include network planning, system design, integration and development, had revenues of $568 million in 2008. (Writing by Toni Vorobyova; Editing by Dan Lalor)