BRUSSELS — Mars, Inc. said it plans to invest €1 billion ($1.18 billion) in its European Union operations by the end of 2026, part of an effort to strengthen the company’s manufacturing capabilities, sustainability and innovation in the region. The investment follows more than €1.5 billion that Mars has invested in EU manufacturing over the past five years. Mars operates 24 facilities across 10 countries in the European Union. Eighty-five percent of Mars’ products sold in the European Union are produced locally, the company said. Earlier this year Mars unveiled plans to invest about $2 billion through 2026 to expand its US-based manufacturing operations nationwide.