Europe's largest dealers and buyside firms may be required to trade certain over-the-counter derivatives on exchanges and other platforms from the moment the region's new trading rulebook comes into force in January 2018, far earlier than many expected and creating possible cross-border headaches.

The European Securities and Markets Authority, the region's major securities watchdog, proposed in a discussion paper published on September 20 to phase in a requirement for certain derivatives to be forced onto trading venues, as part of the EU's revised Markets in Financial Instruments Directive.