A TEN Minute Rule Bill calling for the UK to negotiate a customs union with the European Union has passed its first Parliamentary hurdle after a knife-edge vote in the House of Commons.

The proposal, brought forward by Liberal Democrat Europe spokesperson Al Pinkerton MP, was approved by a single vote on Tuesday after the Commons split 100 votes to 100, with the Deputy Speaker using their casting vote in favour of the Bill proceeding.

The Liberal Democrats described the result as a “historic victory”, arguing it sets an important parliamentary precedent for closer post-Brexit trading ties with the EU.

The vote saw 13 Labour backbenchers break ranks to support the proposal, alongside MPs from the Liberal Democrats and Plaid Cymru. In Wales, six MPs voted in favour, including Plaid Cymru’s Liz Saville Roberts, Ben Lake, Llinos Medi, Ann Davies, and Liberal Democrat MP David Chadwick, as well as Labour’s Tonia Antoniazzi, the MP for Gower.

However, the majority of Welsh Labour MPs chose not to back the measure. Among those abstaining was Henry Tufnell, Labour MP for Mid and South Pembrokeshire, who did not vote either for or against the Bill.

Other Welsh Labour MPs who abstained included representatives from Cardiff, Swansea, Llanelli, Neath, Newport, the Valleys and north Wales constituencies.

Economic impact of Brexit cited

The Liberal Democrats pointed to analysis from the House of Commons Library, commissioned by the party, which estimates the UK is losing around £250m a day in tax revenue as a result of Brexit-related economic impacts.

The party also highlighted concerns about the effect of Brexit on Welsh trade, citing research suggesting the volume of Welsh exports to the EU fell by around 31% between 2019 and 2024, while EU imports into Wales declined by approximately 20% over the same period.

They argue that small and medium-sized businesses in Wales are particularly exposed to additional trade barriers with the EU, given Wales’ historic reliance on European markets.

Speaking after the vote, Welsh Liberal Democrat Westminster spokesperson David Chadwick MP said the result reflected growing pressure for a change in the UK’s trading relationship with Europe.

“Across Wales, people are crying out for real change and a solution to the cost-of-living crisis,” he said. “A customs union with the EU is the single biggest step the government could take to grow our economy, put money back into people’s pockets and generate billions for our public services.”

Government position unchanged

The vote does not change government policy, and Ten Minute Rule Bills rarely become law without government backing. Labour ministers have so far ruled out rejoining the single market or customs union, citing commitments made during the general election campaign.

However, the narrow margin and cross-party support are likely to add pressure on the government as it seeks to “reset” relations with the EU through negotiations on trade, defence and regulatory cooperation.

For Pembrokeshire, where agriculture, food production, tourism and small exporters form a significant part of the local economy, the debate is likely to resonate, particularly among businesses affected by post-Brexit paperwork, costs and delays.

The Bill will now proceed to a second reading at a later date, though its long-term prospects remain uncertain.