CANNES, France — Nokia is forecasting a sharp rise in 3G network subscribers, and is suggesting that at least 70 million subscribers will be using the technology by the end of 2005, up from 16 million at the end of 2004.

The upbeat prediction came as the Finnish handset maker launched three 3G mobile phones and a digital music collaboration with Microsoft Corp.

"We expect that over 100 3G networks will be operating worldwide by the end of 2005," said Simon Beresford-Wylie, executive vice president of Nokia's networks division.

He suggested that a big 3G driver will be music and multimedia downloads. Using this as an opening, Beresford-Wylie unveiled a new partnership with Microsoft that will port the latest version of Windows Media Player to Nokia handsets. The combination will allow music to be transferred between mobile phones and PCs.

The companies stressed the deal only involves collaboration on digital media and audio formats and does not signal that Nokia will use Microsoft's operating system in its phones. Currently almost all Nokia handsets are based on the Symbian platform.

Nokia also unveiled at the 3GSM World Congress here a renewed strategy to increase collaboration with network operators, particularly customizing handsets to their requirements. "Operator customization is now at the heart of our strategy for mobile growth," said Olli-Pekka Kallasuvo, executive vice president of the mobile phones division.

As an early indication of the increasing emphasis on customization, Nokia revealed it has struck an exclusive phone design deal with China Mobile Communications Corp. (CMCC), the world's largest operator of mobile networks. The phone will use the same platform as the 6101 camera phone launched here, but will be customized according to CMCC's specifications.