Westminster reopens relations debate

UK Prime Minister Andy Burnham told the annual Labour Party conference on 29 September 2026 that leaving the European Union had weakened national economic growth and border control. Burnham, who took office during the summer of 2026 after replacing Keir Starmer, stated that the past decade had been characterized by stagnation and division. In subsequent interviews, the prime minister confirmed that his administration is evaluating multiple future arrangements, including entry into a customs union, participation in the European Economic Area, and full EU membership. Burnham indicated that a commitment to hold an in-out referendum could be included in Labour's manifesto for the next general election.

Brexit has done more harm than good.

— Andy Burnham

Polling reveals shifting electorate

A survey of 11,461 UK adults conducted by the Messina Group between 12 and 24 September 2026 recorded 49% support for rejoining the European Union, while 28.5% opposed the move. The polling, published by The Guardian, suggested that pursuing closer European ties could increase Labour's general election vote share by up to seven percentage points, primarily capturing voters from the Liberal Democrats and the Green Party. When questioned on the timetable for returning, 25.9% of respondents favoured immediate accession, 22.9% wanted to rejoin within three years, and 8.4% preferred a horizon over the next decade. Almost a third of respondents indicated that an in-out referendum would be necessary before returning to the bloc, while one in six believed a general election manifesto victory was sufficient.

UK voter support for European Union relationship options (%)
Rejoining the EU49Reducing existing trade barriers48.2Entering a customs union47.1

Trade models and economic performance

The Messina Group poll examined intermediary relationships, finding that 48.2% of voters supported removing trade barriers under the current trade treaty, with 20.9% opposed. A customs union model received 47.1% support against 20.7% opposition, echoing proposals made earlier in September by former Chancellor of the Exchequer George Osborne. Macroeconomic research indicates that UK gross domestic product is between 6% and 8% lower than projected under continued EU membership, representing an annual output loss between £100 billion and £200 billion. Domestic business investment in Britain is 12% to 18% lower than in comparable European economies. Freight volumes across key transport routes have fallen since 2016, with Channel Tunnel truck traffic declining from 1.64 million vehicles to 1.16 million.

Annual Channel Tunnel freight truck volume (million trucks)
20161.6420261.16

European reaction and accession requirements

European leaders delivered initial responses to Burnham's remarks, with French President Emmanuel Macron and Spanish Prime Minister Pedro Sánchez indicating openness to closer cooperation during a joint press appearance. Diplomatic specialists, however, pointed out that any future application for membership would require unanimous approval from all 27 EU member states, followed by national ratifications such as a three-fifths majority in both chambers of the French Parliament. David McAllister, chair of the European Parliament Committee on Foreign Affairs, noted that the 1,200-page Trade and Cooperation Agreement already governs trade, fisheries, law enforcement, and aviation, alongside British re-entry into the Copernicus and Erasmus programs. McAllister cautioned that non-member nations face strict limits on single market access.

A country that leaves the EU cannot enjoy the same benefits as a country that is a member of the European Union.

— David McAllister