The announcement is the first in what is expected to a series of VoIP programs between the pair, on the heels of a joint-technology deal signed last week.
Microsoft chief executive Steve Ballmer reportedly said at a news conference in Paris that the partnerships’ first products would be ready within a year.
Initially, the companies would jointly develop a services platform for voice, video and data.
Beyond triple play, the platform would include side-by-side services so users can combine TV, VoIP, instant messaging and presence, the companies said.
France Telecom plans to aggregate, provision and manage a range of new converged services for consumers and business customers, to enrich and simplify their everyday life, regardless of network or device, read a company statement.
The companies also are plotting a couple of WiFi VoIP phones based on Microsoft software for the home and office. They include a dual radio GSM mobile handset and a broadband smart phone.
Ballmer told reporters the two companies likely would evenly split the cost of developing new products.
There have been other agreements between companies to jointly develop IP-based products. Last month, for instance, Siemens said its IP television would be launched over the phone lines of Dutch operator KPN.