On Wednesday evening, UK MPs voted by 309 votes to 305 to approve amendment 7 to the European Union (Withdrawal) Bill with a view to giving the House of Commons a meaningful vote on the terms of the ‘withdrawal agreement’ currently being negotiated between the EU and the UK under the Article 50 exit process. This defeat for the Government a has been hailed by Conservative rebel MPs and the Labour and other MPs who supported the amendment as the moment that Parliament took back control over the Brexit process.

So what exactly does the amendment do? After this amendment, clause 9 of the Bill will read as follows:

A Minister of the Crown may by regulations make such provision as the Minister considers appropriate for the purposes of implementing the withdrawal agreement if the Minister considers that such provision should be in force on or before exit day, subject to the prior enactment of a statute by Parliament approving the final terms of withdrawal of the United Kingdom from the European Union.

It should be apparent that this new statute will only be required if two conditions are met.

Firstly, and obviously, the new statute is only needed if there is a withdrawal agreement. If the EU and UK fail to agree terms on a withdrawal agreement, then there is nothing for Parliament to approve. In which case the UK would simply leave the EU consequent to the triggering of Article 50, which Parliament authorised when it passed the European Union (Notification of Withdrawal) Act 2017.

Secondly, as an amendment to clause 9, the need for a new statute only arises if a Minister intends to use delegated powers to implement a withdrawal agreement. Yet there is reason to think that this clause may be superseded by moves to put any withdrawal agreement on a statutory footing.

The Institute for Government has previously noted its concerns about the use of a statutory instrument to implement the withdrawal agreement. Particularly given the importance of ensuring that the Citizens’ Rights aspects of the withdrawal agreement have a sound legal footing both in EU and domestic law, primary domestic legislation would always have seemed like a better idea. So back in November the Government announced that a new Withdrawal Agreement and Implementation Bill would be presented to Parliament to legislate for the terms of withdrawal and for any transitional arrangements. More recently, and following the conclusion of Phase One of the withdrawal negotiations, the joint text agreed by the EU and UK reiterated that this new Bill will implement the agreement and fully incorporate the Citizens’ Right part.

All of which does leave one to wonder what is now left to be done by way of statutory instrument under clause 9. And if the answer is nothing, then there is no basis for Parliament to approve by way of statute the terms of the withdrawal agreement.

Parliament would still have it says on the Withdrawal Agreement and Implementation Bill. And the provisions of the Constitutional Reform and Governance Act would be triggered to give both Houses of Parliament oversight of the final deal. But there would be no specific statutory approval of the terms of the final agreement.

The loss of the vote on the amendment does remind us of the weakness of the current government. But that does not necessarily mean that it signals that Parliament has taken back control over Brexit.