Brexit's division still unresolved

A decade on from the United Kingdom making one of the most consequential political decisions in its modern history, the debate over Brexit remains far from settled.

On June 23, 2016, voters in the UK narrowly backed leaving the European Union by a margin of 52 percent to 48 percent, ending more than four decades of bloc membership. Supporters of Brexit, as it is known, promised greater sovereignty, tighter control of immigration, and new global opportunities, but 10 years later, its legacy remains fiercely contested.

Speaking at an event hosted by Chatham House on Monday to mark the anniversary, Michel Barnier, the EU's chief Brexit negotiator from 2016 to 2019, said he has yet to see compelling evidence of any clear benefits resulting from Brexit.

"During the last 10 years, nobody has been able to provide me with proof of any added value from Brexit," Barnier said. He described Brexit as a "lose-lose game", although he cautioned against blaming all of UK's current challenges on leaving the EU.

"I do not believe that all of the UK's current difficulties are linked or provoked by the Brexit," he said. "However, I do think these problems are harder to solve because of Brexit, because the UK has left the single market."

Tom Harper, a lecturer in international relations at the University of East London, said Brexit highlighted the contradiction of UK being "European, but not of it".

"For Remainers, Brexit has not been the catastrophe they often predicted," Harper said. "But for Brexiteers, the promise of Brexit has not come to pass."

According to Harper, Brexit has reduced UK's influence by removing it from decision-making within the EU, although cooperation with European allies has intensified in areas such as defense and foreign policy.

Nando Sigona, director of the Institute for Research into International Migration and Superdiversity at the University of Birmingham, offered a similarly nuanced assessment. He said Brexit increased the UK's formal regulatory autonomy, but reduced its influence over European decision-making.

"Britain remains an important diplomatic and military actor, yet its economic competitiveness and ability to shape regional rules have generally weakened," Sigona said. "Sovereignty was strengthened in a legal sense but arguably diminished in practical terms."

The future relationship between UK and the EU is also evolving. Treasury minister Spencer Livermore recently told the House of Lords that a future return to the EU was "an inevitability" and argued that re-entry would ultimately be in UK's economic interest.

Public opinion also appears to be shifting. Recent polls show a consistent majority of Britons now support rejoining the EU, while younger voters are significantly more pro-European. According to Ipsos, 68 percent of Britons aged 18 to 34 favor rejoining the bloc.

Barnier stressed that any decision would belong solely to UK voters. "The door is open," he said, "but it will be a sovereign choice of the UK people."