In reporting the results of the study, the EU Home Affairs Commissioner Cecilia Malmstroem said the extent of corruption in Europe is "breathtaking" and the true cost of corruption was "probably much higher" than 120bn annually, and that corruption was eroding trust in democracy and draining resources from the legal economy.
Four out of 10 of the businesses surveyed described corruption as an obstacle to doing business in Europe.
Some of the corruption stems from organised crime groups which have sophisticated networks across Europe. The EU police agency Europol says there are at least 3,000 of such crime groups.
Bulgaria, Romania and Italy are particular hotspots for organised crime gangs in the EU, but white-collar crimes like bribery and VAT (sales tax) fraud plague many EU countries.
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