The Chancellor of the Exchequer is the government’s chief financial Minister. The Economic Secretary to the Treasury is the Minister responsible for financial services regulation, including HM Treasury’s relationship with the Financial Conduct Authority (FCA).
The Financial Conduct Authority is an independent non-governmental body responsible for regulating and supervising the financial services industry. Although the Treasury sets the legal framework for the regulation of financial services, it has strictly limited powers in relation to the FCA. In particular, the Treasury has no general power of direction over the FCA and cannot intervene in individual cases.
More information on the roles of HM Treasury ministers can be found at https://www.gov.uk/government/organisations/hm-treasury.