NTT is reported to be considering a bid for the IBM Global Network, which Big Blue put up for sale this month.
According to Japanese reports, the country's largest telco could buy the unit to enhance its international services as deregulation in the industry kicks in around the globe.
However, analysts say NTT does not have a brilliant record in managing international acquisitions. Said Neil Rickard, research director at Gartner Group Europe: "NTT does not have a good record in operating in the industrial market."
The sell-off could raise as much as $4 billion for Big Blue.
Some observers believe the buyer will be a smaller operator rather than a giant such as BT - also expected to be keenly interested - because of antitrust obstacles.
IBM is meeting with analysts this week to outline plans for the future of the Global Network, which grew out of the company's internal telephone and data system and now provides services such as Internet access to corporate clients.
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