Mobile operator Aircel on Wednesday launched a lifetime validity scheme for prepaid mobile customers that is expected to set off a new tariff war, as the plan boasts of call rates as low as 40 paise a minute.

The plan available for Rs 99 would allow users to make local calls at Rs one for the first minute, 60 paise for the second minute and 40 paise for the third minute onwards.

Aircel, a part of Malaysia's Maxis Communication, is India's fifth largest GSM mobile service provider with 17 million users.

It also offers ISD at Rs 1.75 per minute to USA and Canada, along with 300 free messages, as part of this plan.

The plan would also allow users to make Aircel-to-Aircel STD (domestic long distance) calls at 50 paise a minute and the service would be free-of-cost for first three months.