The government has pledged to not use Henry VIII powers to make Brexit legislation after a public law charity threatened legal action.

Public Law Project sent HM Treasury a pre-action protocol letter last week after a statutory instrument was laid empowering officials to amend VAT or customs and excise law by public notice following Brexit.

Henry VIII clauses in a bill enable ministers to amend or repeal provisions in an act of parliament using secondary legislation, by way of statutory instruments, which are subject to varying degrees of parliamentary scrutiny.

The charity argued that the Cross-border Trade (Public Notices) (EU Exit) Regulations 2019 went beyond the powers of its parent act, the Taxation (Cross-border Trade) Act 2018.

The charity acknowledged that Brexit represented exceptional legislative change and challenge. But 'whatever the demands that Brexit poses, and whatever latitude it may require from the courts, it cannot allow the executive to assume or purport to confer on public officials powers to dispense with the law not been clearly and expressly granted by parliament'.

Responding to PLP's letter yesterday, HM Revenue & Customs said the regulations were part of legislation to ensure that, in the event of a no-deal Brexit, the UK had a functioning customs, VAT and excise regime in place on exit day.

HMRC said: 'As is clear the regulations are designed to ease the flow of trade and to allow flexibility. However, we have very carefully considered the points you raise in your letter and, on reflection, we have decided to revoke the regulations. As I am sure you will appreciate due to pressure on parliamentary time, it is not possible to say exactly when these regulations will be revoked. However, HMRC undertake not to use the powers in these regulations before exit date.'

PLP said it was told by HMRC's legal team today that the government has treated the regulations as 'revoked with immediate effect'.

Jo Hickman, PLP director, said: 'The Henry VIII powers laid out in this regulation would have allowed unelected officials to amend laws by decree and without oversight from Parliament. That is wrong in principle and in this case, unlawful.

'The use of public notices in this way has been likened to making law by proclamation as in the time of Henry VIII. Introducing a power to change the law completely outside of the parliamentary process would set a dangerous and undemocratic precedent. The Statute of Proclamations 1539 was repealed after the death of Henry VIII for good reason.'

Meanwhile, prime minister Boris Johnson and EU Commission president Jean-Claude Juncker confirmed that a Brexit deal has been agreed. MPs will vote on the deal on Saturday.