LONDON (Reuters) - Global stocks eased on Wednesday on uncertainty over Canada’s position in NAFTA, and with investors also nervous ahead of a deadline for the next round of China-U.S. tariffs next week. FILE PHOTO: A worker walks in a container area at a port in Tokyo, Japan January 25, 2016. REUTERS/Toru Hanai/File Photo Talks to renew a NAFTA trade agreement between the United States, Mexico and Canada - after Monday’s U.S.-Mexico deal - hinge on Canada’s agreement.