"Leaving the EU gives us a golden opportunity to reshape our regulatory regime and unleash the full potential of our formidable financial services sector," finance minister Jeremy Hunt said in a statement on Thursday ahead of the announcement.
The reforms which Hunt said will "turbocharge" growth in the face of recession and a cost of living crisis, take advantage of Britain's European Union exit to tailor its own rules.
Now dubbed the "Edinburgh Reforms", the proposed reset had been trailed as "Big Bang 2.0", a reference to the 1980s share trading overhaul, raising expectations of a big deregulatory push which left banks fearing costly systems changes.
Britain's Finance Ministry said on Thursday it wants proportionate rules based on best international practice that balance burden on business with protection for consumers.
The reforms include releasing banks without major investment activities from rules requiring them to "ringfence" their retail arms with a bespoke cushion of capital, it said. They follow recommendations from a government-backed review.
Banks have lobbied to either scrap the rule or significantly raise the deposits threshold which triggers the requirement.
There will be a plan to "rigorously review, repeal and replace" EU regulations ranging from disclosure for financial products, listing requirements and prudential rules for banks.
London has been largely cut off from the EU by Brexit, putting pressure on the government after Amsterdam overtook the British capital to become Europe's top share trading centre.
The EU is also updating financial rules to deepen its own capital market and reduce remaining reliance on London.
Britain has already set out initial reforms in its financial services and markets bill being approved in parliament.
Scrapping a cap on banker bonuses and easing capital rules for insurers had already been announced, with a public consultation on regulating crypto assets also flagged.
Hunt is also expected to issue a "new mandate" to regulators on how they will help deliver growth and promote the financial sector's international competitiveness.
Bank of England director Phil Evans said on Wednesday that being a global financial centre confers an array of benefits on the British economy, but also responsibilities such as resisting pressure to "cut standards in the short term".
(Reporting by Huw Jones; Editing by Alexander Smith)
By Huw Jones