- The Northern Ireland Protocol destabilizing the region's political balance in 2021, while calls for independence have grown in the much more pro-EU Scotland

- Post-Brexit, the war in Ukraine and threat from Russia have ‘pushed EU defense cooperation forward’ in the UK, Spatafora tells Anadolu

LONDON

Proponents of Britain's departure from the EU have long argued that the move would secure greater freedom and economic opportunity in the UK. But half a decade later, many of its challenges remain unresolved, as trade disruptions, political divisions, and economic uncertainty continue to shape the country’s post-EU reality.

While security cooperation has remained strong with the bloc, economic and trade hurdles still weigh heavily on Britain's prospects.

However, one thing is clear: Brexit is far from "done." It remains an ongoing reality that will shape UK-EU relations for years to come.

In 2020, then-Prime Minister Boris Johnson’s government officially led the UK out of the EU under the promise to "Get Brexit Done."

The country also left the EU’s single market and customs union a year later, severing nearly half a century of economic integration.

A report from UK in a Changing Europe reveals that many of Brexit’s supposed solutions remain unaddressed — or have worsened.

From economic downturns to unresolved legal and devolution issues, Brexit’s legacy continues to shape the UK’s political and economic landscape.

Now, with the Labour government under Keir Starmer calling for a "reset" of UK-EU relations, a key question emerges: What will the future of Brexit really look like?

Harsh reality of post-Brexit trade

The biggest and most immediate impact of Brexit has been on trade, with a noticeable decline in UK-EU commerce, the report found.

Increased border checks, customs paperwork, and regulatory divergence have made exporting to Europe more costly and complex for UK businesses.

Giuseppe Spatafora, a transatlantic relations expert at the European Union Institute for Security Studies (EUISS), sees these consequences as entirely predictable.

"Leaving the largest economic bloc would necessarily mean major adjustments in national trade, investment, and foreign policy. That is what happened.

"The biggest effects have been on trade, and they have not been positive for London. The UK is struggling to set up a new trade relationship with the EU, but it isn’t clear which model will be followed," he said.

Unlike the Swiss, Norwegian, or Canadian models — which maintain varying degrees of EU access — Britain’s current trade relationship remains uncertain.

The Starmer government has ruled out rejoining the EU but seeks a "closer partnership" to ease economic disruptions.

Key legal ordinances, including the withdrawal deal agreed in 2019 and the Trade and Cooperation Agreement, remain unchanged for now.

Brexit’s lingering legal headaches

One of Brexit’s less anticipated effects has been its impact on devolution and regulatory frameworks.

The UK’s exit from the EU has created tensions between Westminster and devolved governments in Scotland, Wales, and Northern Ireland.

The 2021 Northern Ireland Protocol, initially signed under Johnson, created a de facto trade border in the Irish Sea, enraging unionists and destabilizing the region's political balance.

Rishi Sunak’s Windsor Framework two years later was meant to ease tensions, but political uncertainty lingers.

There has also been growing frustration in Scotland, with Brexit strengthening calls for independence — particularly as voters in the country had overwhelmingly preferred to remain in the EU in the 2016 referendum.

Meanwhile, regulatory divergence between the UK and EU has complicated trade and business operations, making it harder for British firms to access European markets.

Despite five years of negotiations, these legal and structural hurdles remain unresolved, creating a complex web of economic and political challenges.

Defense: A rare area of UK-EU cooperation

While Brexit has strained UK-EU economic relations, security and defense cooperation has remained largely unaffected.

The UK, as a leading NATO power and a key player in European security, has continued working closely with EU allies.

"The UK was seen as a brake on EU defense integration, and some expected its withdrawal to accelerate the Common Security and Defense Policy (CSDP).

"However, it was not Brexit but rather the war in Ukraine and the threat from Russia that pushed EU defense cooperation forward. If anything, these events have brought the UK and EU closer together," Spatafora explained.

Despite no longer being part of EU defense mechanisms, the UK remains a strong military ally of Europe, especially in its support for Ukraine against Russian aggression.

US President Donald Trump’s return to the US presidency also raises concerns about transatlantic stability, making closer EU-UK security cooperation more likely.

Labour’s ‘reset’ for Brexit relations

The UK's current Labour government is not aiming to reverse Brexit, but it does seek a more pragmatic relationship with the EU.

While rejoining the single market or customs union has been ruled out, Starmer's government is expected to pursue regulatory alignment to reduce trade friction, stronger security cooperation, and new agreements on worker mobility.

However, the EU remains cautious. While Brussels is open to closer ties, there is little appetite among member states to renegotiate major treaties.

While Brexit regret — "Bregret" — has grown among the public, rejoining the EU is a distant possibility at best, though polls suggest a growing number of Britons feel Brexit was a mistake, particularly younger ones who were not old enough to vote in 2016.