The European Commission has said for the first time that it is considering a delay of a year to Europe’s overhauled trading rulebook, after its top markets regulator raised concerns over the time needed to put the rules into practice.

The comments came at a scrutiny hearing for the revised Markets in Financial Instruments Directive, or Mifid II, held by the European Parliament's Committee on Economic and Monetary Affairs, known as Econ, in Brussels on November 10.