London Stock Exchange chief executive Xavier Rolet has said Europe's fund managers will have to put in a "very, very big effort" to be ready for new EU trading rules set to take force on January 3.

Speaking at a panel discussion at a Paris conference today hosted by the European Securities and Markets Authority, Rolet said while banks were largely ready for the new rules, having conducted lots of testing, investors would have to work hard to ensure their readiness for the update to the Europe’s Markets in Financial Instruments Directive.