Trade Secretary says Boris Johnson’s Brexit border plans could help smugglers and be vulnerable to WTO challenge

Leaked letter shows Liz Truss has concerns about government’s approach

Liz Truss wrote that she had ‘key areas of concerns’ about the PM’s plans for Northern Ireland (AFP/Getty)

Boris Johnson’s Brexit border plans may be vulnerable to international legal challenge and will help smugglers, the international trade secretary has warned in a leaked cabinet letter.

Liz Truss wrote to Rishi Sunak, the chancellor, and Michael Gove, the chancellor of the Duchy of Lancaster, saying she had “key areas of concerns” about the prime minister’s plans for Northern Ireland.

In the letter, obtained by the Business Insider website, the international trade secretary says the UK would “be vulnerable to WTO challenge” over the plan.

Her comments echo concerns from Brussels, which says Mr Johnson’s plans not to impose controls on goods travelling from Northern Ireland to Great Britain do not stand up to scrutiny and amount to backsliding on what he signed up to in January.

While both the EU and UK agreed to the withdrawal agreement at the beginning of the year, disputes about how it should be implemented in practice have emerged in the months since.

The withdrawal agreement signed by Mr Johnson says the UK will impose the EU customs code, which includes exit summary declarations for goods travelling to Great Britain – but the UK does not want to impose them.

The government is now arguing that such controls would upset unionist politicians and undermine long-term support for the agreement it signed.

In the leaked letter, Ms Truss told her colleagues: “We need to ensure that the UK border is effective and compliant with international rules, maintaining our credibility with trading partners, the WTO and with business.”

The government did not deny the letter’s veracity, and a spokesman said: “We do not comment on leaks.”

Rachel Reeves, shadow chancellor of the Duchy of Lancaster, said: “This email confirms fears that several ministers have been making things up as they go with a lack of awareness of the real world consequences of border policies they’ve had four years to develop.

“At the general election, people were promised an ‘oven-ready’ deal to be implemented by the end of this year, not chaos, confusion and a further risk to jobs.”