The implementation of MiFID II has been formally delayed until 3 January 2018 by the European Commission.
It was previously mooted by stakeholders and regulators last year that the new rulings should be held back in order to allow firms more time to comprehend technology challenges and comply with the regulations.
This was supported by the Financial Conduct Authority but needed to be formally confirmed by the European Parliament.
It was felt that the previous deadline of January 2017 was "unfeasible" and "not ideal" for firms to meet given the volume of regulation.
The European Commission said the deadline had been moved in order to "take account of exceptional technical implementation challenges", which were faced by those involved.
Baringa Partners partner James Nicholls said: "It is critical that all parties are given the time to get the job done properly, rather than forcing through half-baked measures.
"The post-implementation experience with EMIR has certainly focused the minds of both regulators and practitioners on the folly of ‘going live' with significant operational questions still unresolved."
He added: "The likely delay will give firms time to push on with MiFID II implementation but this should not be an excuse to lose momentum on the reform drive.
"Firms can now take a more strategic and measured approach to how they approach these issues but the scale and intensity of the transformation needs to continue."
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