Research In Motion and Apple Inc's duopoly in the smartphone market will be pressured by other handset makers eager to capture share, the head of Canada's biggest wireless carrier said on Tuesday.

Rob Bruce, the president of Rogers Communications' wireless business, said he expects that phones with full slideout keyboards, as well as those based on Google's Android operating system, will chip away at the dominance of RIM's BlackBerry and Apple's popular iPhone.

(Reporting by Wojtek Dabrowski; editing by Peter Galloway)