The head of the Trades Union Congress has urged Prime Minister Sir Keir Starmer to consider negotiating a new customs union with the European Union, arguing that reducing post-Brexit trade frictions is necessary to protect jobs and ease rising costs for households and businesses.

Paul Nowak, general secretary of the TUC, said the government should examine “every option” for improving the UK’s relationship with the EU, “up to [and] including a customs union”, in comments reported by the Financial Times. He said additional checks and paperwork introduced since Brexit were weighing on exporters, discouraging investment and feeding through into prices.

The intervention adds to pressure on Labour’s leadership as it pursues a limited “reset” of relations with Brussels while maintaining longstanding “red lines” against rejoining the single market, the customs union and free movement of people. Starmer has repeatedly argued those steps would constrain the UK’s ability to strike and implement independent trade agreements with countries outside Europe.

Nowak framed closer EU alignment not only as an economic issue but also as part of a broader strategy for security and diplomacy. “The last 12 months have proven that the White House is not the reliable ally that we thought it always was … you’ve got to have the right relationship with your largest trading partner,” he said, according to the Financial Times.

A customs union would remove the need for rules-of-origin paperwork on goods traded between the UK and EU and could reduce some border friction by aligning external tariffs, but it would also limit the UK’s freedom to diverge on trade policy because the country would need to apply a common tariff regime on imports from the rest of the world.

Labour has sought to improve day-to-day trading arrangements within the framework of the EU-UK Trade and Cooperation Agreement, which has governed relations since 2020. In May this year, the UK and EU announced a limited package aimed at reducing red tape in areas such as food trade, carbon markets and certain regulatory processes, without reopening the core deal.

However, unions and parts of business have continued to argue that the existing arrangements do not go far enough to address the costs created by Brexit-related checks. Recent surveys cited by the Financial Times suggest dissatisfaction remains widespread among exporters, with 53% describing the current trade deal as unsatisfactory.

Nowak also used the intervention to press the government on related parts of Labour’s policy agenda, including a youth mobility agreement with the EU and stronger enforcement of workers’ rights. He warned against any dilution of Labour’s planned Employment Rights Act proposals, an area the unions regard as a central part of the government’s domestic programme.

The TUC is the UK’s main umbrella body for trade unions, representing about 47 affiliated unions. Its public call for a customs union is significant because Labour has historically maintained close ties with organised labour, even as Starmer has sought to project a cautious approach to Brexit to avoid reopening political divisions.

The comments also come amid signs of debate inside Labour over how far the government should go in reducing barriers with the EU. Wes Streeting, the health secretary, has recently spoken favourably about a customs union, according to reporting in The Times, highlighting tensions between those pushing for deeper integration and those intent on holding to the party’s existing commitments.

Downing Street has previously said that the government’s approach is to pursue improved practical co-operation with the EU while keeping its Brexit “red lines” in place. Ministers have argued that the UK can secure targeted arrangements that benefit key sectors without committing to structures that would bind the country to EU trade policy.

Economists and analysts have continued to debate the scale of Brexit’s long-term impact. Some estimates cited in recent political reporting put the hit to long-run UK GDP growth at around 3%, while critics of the current approach argue that incremental changes are unlikely to reverse the underlying drag on trade and investment.

Nowak’s call is likely to intensify scrutiny of whether the government will maintain its current stance as pressure builds from unions and some senior figures to pursue a deeper trade settlement with the UK’s largest trading partner. It remains unclear how receptive EU institutions would be to customs union talks, which would represent a substantial change in the structure of post-Brexit relations.