Reliance Communications chairman Anil Ambani and Microsoft CEO Steve Ballmer are expected to make a joint announcement on when the latter arrives is in India on Monday, according to a report.

Reliance Communications is planning to launch IPTV services in Mumbai and Delhi by the end of this year, and had finalised the technology for this.

Reliance Communications, meanwhile, is set to reduce mobile phone charges by a third with the launch of its pan-India GSM telecom services.

The company is planning to minimise the difference in the Rs1.11 a GSM subscriber pays for every minute of a call he makes with the Rs0.85 a CDMA subscriber pays for a minute of call time.

This 33 per cent differential is what Reliance Communications plans to leverage as it rolls out of its GSM services, for which it got a licence last month. Reliance Communications already has a nationwide CDMA network.

Ambani told an analysts'' conference on Thursday that his company''s GSM expansion would leverage existing infrastructure and the dual network for cheaper tariffs.

Mahanagar Telephone Nigam Ltd and private sector Bharti Airtel have already launched IPTV services, while several other operators are in the process of rolling out these services.