Research in Motion, the maker of the BlackBerry is understood to be planning a touch-screen version of its popular mobile email device.

The Wall Street Journal reports the BackBerry Thunder will launch in the third quarter, and is likely to be sold through mobile operator Vodafone in the UK.

RIM has been hinting about a touch-screen model since earlier this year, and it would represent a direct challenge to the threat of Apple's iPhone.

The iPhone has hitherto been primarily a consumer device, while the BlackBerry counts armies of corporate employees among its user base. Nevertheless, the next-generation iPhones are expected to be more business friendly, and RIM seems to be taking proactive steps to safeguard its market share.

Earlier this week RIM unveiled its new BackBerry Bold, which comes with a half VGA 480 x 320 screen and support for high-speed HSDPA networks.