BERLIN, July 4 (Reuters) - A majority of German firms operating abroad are more optimistic about their business than they have been in a long time, a survey of the DIHK chambers of commerce showed on Tuesday.

Some 56 percent of the 4,000 firms surveyed by DIHK said they expected better business over the next 12 months and more than a third said they expect the economies in their host countries to improve.

Despite the optimism, a record high of 50 percent said they considered political risks as a top threat to their business over the next 12 months. Britain's divorce negotiations with the European Union, U.S. trade policies and protectionism were named as major risks. (Reporting by Gernot Heller; Writing by Joseph Nasr; Editing by Madeline Chambers)