The United Kingdom’s Post-Brexit Realignment: Trade, Finance and the Search for a New Global Role

Expert Comment — Europe Programme

22 January 2026

Five years after the conclusion of the Trade and Cooperation Agreement with the European Union, the United Kingdom’s post-Brexit economic and strategic realignment remains very much a work in progress. The government’s flagship “Global Britain” agenda has achieved some notable successes — including accession to the Comprehensive and Progressive Agreement for Trans-Pacific Partnership and new trade agreements with Australia and New Zealand — but the economic costs of leaving the EU have been higher and more persistent than Brexit proponents anticipated, while the strategic benefits remain difficult to quantify.

The Office for Budget Responsibility’s latest assessment estimates that Brexit has reduced UK GDP by approximately 4 per cent relative to a counterfactual of remaining in the EU. Trade frictions with the UK’s largest trading partner have reduced goods trade by an estimated 15 per cent, while new non-tariff barriers have particularly affected smaller businesses and the agricultural sector. Services trade, long touted as an area of British comparative advantage, has also underperformed, as the anticipated “Singapore-on-Thames” deregulation has not materialised to the extent proponents hoped.

Financial services, the crown jewel of the British economy, have shown greater resilience than many predicted. London remains Europe’s leading financial centre, though its share of euro-denominated derivatives trading has declined, and Frankfurt and Paris have captured some business. The City’s ability to adapt its regulatory framework independently of the EU has been presented as an advantage, but this has yet to translate into significant new business from outside Europe.

The resolution of the Northern Ireland Protocol dispute through the Windsor Framework in 2023 removed a significant source of political and economic uncertainty. The framework’s “green lane” and “red lane” system for goods moving between Great Britain and Northern Ireland has reduced, though not eliminated, trade frictions. More importantly, it has stabilised the political situation in Northern Ireland, enabling the restoration of power-sharing institutions.

The UK has positioned itself as Europe’s leading defence power following Russia’s invasion of Ukraine. Defence spending has been increased to 2.5 per cent of GDP, and the UK has been one of the largest military aid donors to Ukraine. The AUKUS partnership with Australia and the United States represents a significant strategic bet on the Indo-Pacific, though it has come at the cost of damaging relations with France and the broader European defence project.

The United Kingdom’s post-Brexit trajectory is neither the disaster its opponents predicted nor the triumph its proponents promised. The economic costs have been real but manageable. The strategic benefits — greater flexibility in trade policy, an independent defence posture, the ability to chart an independent regulatory course — are real but modest. The fundamental challenge facing British policymakers is that the benefits of Brexit were always more about sovereignty and democratic control than about economics, and these are inherently difficult to measure. In the long run, the success or failure of the Brexit project will be determined not by trade statistics but by whether the UK can build a domestic economic model that delivers broadly shared prosperity.