The London Stock Exchange Group, nine trade bodies and four of the world's largest asset managers have united in an unusual last-ditch attempt to influence key rule changes to Europe's securities markets, including a new approach to the oversight of controversial dark pools.

An unlikely coalition including the LSE, bank lobby the Association for Financial Markets in Europe and fund managers BlackRock and Fidelity, wrote a letter to the EU's key legislative bodies yesterday raising concerns over revisions to the EU's 2007 Markets in Financial Instruments Directive, dubbed Mifid II.