Google will stop supporting prepaid cards for Google Wallet, with the web giant phasing them out over the next few months.

The company recently changed how its mobile app stores payment cards, effectively moving payment card information from the device to its cloud, and allowing customers to use almost any credit or debit card . Previously, the Wallet app only supported Citi's MasterCard and Google's own prepaid cards.

These changes have led Google to begin phasing out prepaid cards, as they are no longer necessary. The company sent its users an email today with the deadlines for when it will stop accepting the cards.

On September 17, 2012, Google will remove the ability for users to add prepaid cards to the Wallet app. This will also mean that any existing prepaid cards that are removed from app after this date can't be added again.

Users will have until October 17, 2012, to spend their remaining balance. After this date, cards will disappear from the app completely, rendering any remaining balance unusable.

The discontinuation of the cards will likely not affect most US residents. However, in other countries, the Google Wallet app and US cards are not officially supported, which may have repercussions for early adopters. In many cases, these users have been using prepaid cards and modified versions of the Wallet app to get around the lack of support for local credit and debit cards, but the elimination of prepaid cards will remove the sole method they have of adding funds to the Wallet app.

Despite the app being out for almost a year now, Google still has no timing on when it will be made available outside of the US.