NTT DoCoMo Inc. has formed a partnership with counterparts in China and South Korea to accelerate the spread of smart phones in the region.

DoCoMo said Tuesday it plans to work closely with China Mobile Ltd. and KT Corp. in developing infrastructure technology for high-speed communications, while aiming to expand corporate service business in Asia.

Last month DoCoMo launched a high-speed data communications service for mobile phones, dubbed Xi (pronounced "crossy").

China Mobile and KT forged a partnership in November and sounded out DoCoMo about a possible deal.