Assessments of Britain's future access to the European Union financial market are ongoing and take into account how far the United Kingdom will diverge from the bloc's rules, a European Commission official said on Wednesday.
Britain left the EU in January and retains full access to the EU until the end of December under a transition deal.
Future access for banks, clearing houses and trading platforms will depend on Brussels deciding that Britain's financial rules are and likely to remain equivalent to or sufficiently aligned with those in the bloc.
"We need to have a forward-looking approach and have a good understanding of the intentions the UK has in terms of future financial regulation," Andrea Beltramello told an online event organised by the Futures Industry Association, an industry body.
Britain and the EU have blamed each other for missing an end of June deadline to complete assessments on financial market access from next January.
The London Stock Exchange's London Clearing House unit clears over 90% of euro-denominated interest rate swaps and said it needs certainty on EU access by September to avoid forcing customers to move positions out of Britain by December.
Julien Jardelot, the LSE's head of Europe government relations and regulator strategy, said he hopes the EU can give some form of legal clarity shortly.
"We are confident that both EU and UK regulators... understand the need to ensure a smooth transition," Jardelot said.