BARCELONA  - China's Huawei, the number three smartphone maker behind giants Samsung and Apple, unveiled a new mobile, the Ascend P2, which it claims is the world’s fastest. Sharp-cornered and thinner than a pencil at 8.4 mm, the company said it can achieve speeds of 150 Mbps, fast enough to download a two-hour high-definition movie in less than five minutes. The mobile, which has a 4.7-inch, HD screen, has a powerful 1.5 GHz quad-core processor and is able to use the fourth-generation high speed mobile networks. Unveiling the device on the eve of the opening Monday of the four-day Mobile World Congress in Barcelona, Spain, the company said it was "the world's fastest smartphone".