UPDATE 3-Huawei's U.S. research arm slashes jobs as trade ban bites

SANTA CLARA, Calif./HONG KONG, July 23 (Reuters) - China's Huawei Technologies laid off more than two-thirds of the 850-strong workforce at its Futurewei Technologies research arm in the United States, after being blacklisted by the government. Futurewei, which has offices in Silicon Valley and the greater Seattle, Chicago and Dallas areas, said it cut more than 600 jobs.