LG Electronics Inc., the world\'s third-largest handset maker, said Tuesday that it will release a new smartphone that runs on the high-speed, long-term evolution (LTE) networks via AT&T Inc. The upcoming smartphone will be LG\'s second LTE handset in the U.S., LG said in a statement. LG has been rushing to beat rivals in the fourth-generation (4G) wireless market after losing significant ground in the third-generation smartphone race. LG\'s mobile business posted a six straight quarterly loss through the third quarter. Though it was a latecomer in the smartphone market, LG hopes to narrow the gap with market leaders as mobile carriers around the world begin services of 4G networks to meet demand from data-gobbling smartphone users. AT&T said it will launch the LG Nitro HD smartphone, also known as the Optimus LTE, on Dec. 4. The smartphone will be available for customers at US$249 with a two-year contract. The upcoming smartphone features a high-definition 4.5-inch screen that displays vivid and natural color, LG said. The Android-based smartphone is powered by a dual-core 1.5 gigahertz processor.