Reuters reports that a senior Financial Conduct Authority (FCA) official told lawmakers that diverging from the EU's securities rules would be the "exception" rather than the rule.

"Areas where we would diverge are the exception rather than the rule," Edwin Schooling Latter, FCA executive director for wholesale markets, told a parliamentary committee.

Britain left the EU in January and full access to the bloc's single market for UK financial firms ends on Dec. 31.