The European Parliament's influential Economic and Monetary Affairs Committee has expressed concerns that banks and HFTs could come together and effectively set up unregulated trading venues in the region.

Econ's chairman Roberto Gualtieri and his vice-chair Markus Ferber have written to Valdis Dombrovskis, vice-president of the European Commission, to call for further investigation into potential "circumvention" of trading rules under the EU's revised Markets in Financial Instruments Directive.