UK Reviews US and EU Proposals Before Finalising IMA Rules

The Bank of England is reviewing regulatory proposals from United States and European Union authorities before finalizing its rules for the Internal Models Approach (IMA) under the Fundamental Review of the Trading Book (FRTB). The move aims to ensure international consistency in how banks calculate market risk capital requirements, reducing the regulatory burden for firms operating across multiple jurisdictions.

The development was highlighted during the International Swaps and Derivatives Association (ISDA) Annual General Meeting held in Boston, where officials addressed the challenges of implementing the Basel III capital framework. The FRTB is a critical component of these rules, specifically governing how banks measure the risk of their trading books to determine the amount of capital they must hold against potential losses.

Pursuit of International Consistency

David Bailey, the executive director for prudential policy at the Bank of England, emphasized that aligning the UK’s approach with other global financial hubs is essential for the stability of cross-border finance.

International consistency matters. It underpins cross-border business and the ability of firms to interact on a global basis,

David Bailey, executive director for prudential policy at the Bank of England

The IMA is a sophisticated method that allows banks to use their own internal risk models to calculate capital requirements, rather than relying on a standardized approach. However, because these models can vary significantly between institutions, regulators in the UK, US, and EU have struggled to agree on a uniform set of standards for validating and approving these models.

Discrepancies in how these rules are applied can lead to regulatory arbitrage, where banks shift activities to jurisdictions with more lenient capital requirements. By reviewing US and EU proposals, the Bank of England seeks to avoid creating a divergent regime that could disadvantage UK-based firms or create operational complexities for global banks.

Impact on Capital Requirements

The finalization of the IMA rules will have a direct impact on the balance sheets of the largest financial institutions. Banks that successfully implement and have their internal models approved under the FRTB framework may be able to optimize their capital usage, potentially lowering the amount of capital they are required to set aside for market risk.

Conversely, if the Bank of England adopts more stringent requirements than its peers in the US or EU, UK banks could face higher capital charges, which may influence their trading strategies and the pricing of derivatives and other financial instruments.

The Bank of England previously announced its final Basel III rules in January 2026, while the European Union has provided its own outline for the Basel endgame proposals. The current review of the IMA specifically targets the nuances of market risk implementation to ensure the UK remains competitive while maintaining prudential safety.

Global Regulatory Outlook

The effort to synchronize these rules comes amid broader uncertainty regarding the timing and exact nature of the Basel III implementation globally. While the Bank of England has expressed confidence that regulators are on track to implement the rules in a broadly consistent manner, the process involves reconciling different supervisory philosophies across the Atlantic and within Europe.

Industry participants at the ISDA AGM noted that the alignment of IMA rules is a primary concern for the banking sector. A fragmented regulatory landscape would force global banks to maintain multiple, differing capital calculation engines for different regions, increasing compliance costs and operational risk.

The Bank of England’s decision to wait for and review the specific proposals from the US and EU before finalizing its own IMA rules suggests a strategic preference for a multilateral agreement over a first-mover advantage in regulation.