On Thursday 17 October, the Prime Minister and the European Council announced they had agreed in principle a revised EU exit deal. On Saturday 19 October, there will be an extraordinary sitting of both Houses of Parliament so that MPs can approve, and Peers debate, the implications of this new deal.

Why is Parliament sitting on a Saturday?

Saturday is the last opportunity that the Prime Minister has to avoid having to ask for an extension of Article 50 under the European Union (Withdrawal) (No. 2) Act 2019 (also known as ‘the Benn Act’).

MPs approved (with amendment) a Government proposal (called a Business of the House order) on Thursday 17 October to allow this Saturday sitting to happen.

Parliament has not sat on a Saturday since on 3 April 1982, following the invasion of the Falkland Islands.

What will Parliament do on Saturday?

MPs will meet at 9:30am, like they do when they sit on Fridays. There will first be a statement from the Prime Minister (presumably setting out the Government’s position in the aftermath of the European Council summit). The Commons will then proceed to debate either one or two motions that have been tabled by the Government.

The motions will be amendable, since they are both “substantive” propositions. We expect that the debate will end at around 2:30pm, although the debate on the motions is not time-limited and, depending on the progress of business on the day, the House might not “rise” until slightly later in the afternoon.

The House of Lords will also sit on Saturday, from 10am. Although it will debate the implications of the Government’s revised arrangements for the UK’s EU withdrawal, it will not take any “decisions” about what should happen next.

What does the Prime Minister have to do to avoid asking for an extension?

There are two “routes” by which the Prime Minister can avoid the ‘Benn Act’s’ legal obligation to ask for an extension of Article 50 until 31 January 2020.

One option is that he could secure the approval of MPs for his revised EU exit deal. His alternative option is to secure the approval of MPs for leaving the EU without a deal. Either of these options, however, require MPs to debate and vote on a motion by Saturday.

As can be seen from the Order Paper for Saturday, the Government has left open the option of having debates on either or both of these proposals.

One motion for debate says:

‘That, in light of the new deal agreed with the European Union, which enables the United Kingdom to respect the result of the referendum on its membership of the European Union and to leave the European Union on 31 October with a deal, and for the purposes of section 1(1)(a) of the European Union (Withdrawal) (No. 2) Act 2019 and section 13(1)(b) of the European Union (Withdrawal) Act 2018, this House approves the negotiated withdrawal agreement titled Agreement on the withdrawal of the United Kingdom of Great Britain and Northern Ireland from the European Union and the European Atomic Energy Community and the framework for the future relationship titled Political Declaration setting out the framework for the future relationship between the European Union and the United Kingdom that the United Kingdom has concluded with the European Union under Article 50(2) of the Treaty on European Union, as well as a Declaration by Her Majesty’s Government of the United Kingdom of Great Britain and Northern Ireland concerning the operation of the Democratic consent in Northern Ireland provision of the Protocol on Ireland/Northern Ireland, copies of these three documents which were laid before this House on Saturday 19 October.’

Whereas the other says:

‘That this House approves the withdrawal of the United Kingdom from the European Union under Article 50 of the Treaty on European Union on exit day, without a withdrawal agreement as defined in section 20(1) of the European Union (Withdrawal) Act 2018.’

The deal motion

The first motion serves two purposes in legal terms. One is to try to meet the requirements of the ‘Benn Act‘ and avoid asking for the further three month extension. The second purpose is to satisfy part of section 13 of the EU (Withdrawal) Act 2018’s prerequisites for ratification of a withdrawal agreement treaty: a so-called “meaningful vote”. Passing this motion without amendment fulfils both legal hurdles.

There are three amendments on the order paper (and given the time pressures, the Speaker might consider additional “manuscript” amendments on the day). All three on the Order Paper propose to withhold approval for the revised deal.

Amendment (b) (from Angus MacNeil MP) calls for the revocation of Article 50 instead;

Amendment (c) (from Ian Blackford MP) calls instead for an extension to allow a general election to happen; and

Amendment (a) (from Sir Oliver Letwin MP) withholds approval unless and until implementinglegislation has passed.

Other possible amendments might leave it legally uncertain whether the House has approved the withdrawal agreement: for example, if MPs sought to make approval conditional on a further referendum. It will be up to the Speaker to decide which amendments, if any, will be eligible to be moved for decision.

The no-deal motion

We would not expect the no-deal motion to be moved if MPs approve the Prime Minister’s EU exit deal. It also seems unlikely that this motion will be the subject of any amendment if it is moved. This is because, under section 1(2) of the ‘Benn Act’, the motion has no legal effect if it is amended.

What if neither motion passes?

If neither motion passes on Saturday, the ‘Benn Act’s’ provisions kick-in. The Government has no discretion about whether to ask for an Article 50 extension. It also has no discretion around the length of extension to request. The Prime Minister would have to write to European Council President Donald Tusk, asking for an extension until 31 January 2020.

In that scenario, an extension seems likely to be offered for the purposes of either enabling a general election to take place, or for some other major rethink of the Brexit process. If the Letwin amendment passes, however, the Government might still look to bring forward the implementing legislation, discussed below.



There is no guarantee that an extension would be offered for whatever purpose. Furthermore, both the extension and its length would need to be agreed unanimously by the 27 other EU Member States. The Prime Minister could only “modify” or “withdraw” his extension request if he subsequently persuaded MPs to approve a withdrawal agreement or leaving without a deal.

If offered an extension by the EU to 31 January 2020, the Prime Minister would have to accept it. If offered either a longer or a shorter extension, he would have to either agree to it within two days (or in any case before 31 October) or persuade MPs to “decide not to approve” the extension before then.

In the absence of an extension or a deal, the UK would leave the EU by default on 31 October 2019, unless it revoked Article 50 unilaterally.

What if the deal motion passes?

If the motion to approve the revised agreement is passed, Parliament’s attention will then turn to passing an implementing Act of Parliament: the European Union (Withdrawal Agreement) Bill. This legislation has to pass to meet the condition set out in section 13(1)(d) of the EU (Withdrawal) Act 2018 for ratifying the treaty.

In the EU, attention will turn to its side of the ratification process. It is not enough for the European Council formally to sign-off (by qualified majority) on the deal: the EU must also get the consent of the European Parliament.

Both of these ratification processes could (in theory) be completed against an accelerated timetable. Jean-Claude Juncker, the President of the European Commission, appeared to question why there would need to be an extension given that a deal has been agreed in principle. However, in practice, the UK Government and the EU may conclude that a short or “technical” extension is desirable, perhaps of a few weeks, to ensure the smooth completion of their respective ratification procedures.

The critical difference in that scenario would be that the UK Government would be choosing to seek an extension of Article 50 and would have discretion about the length of extension it was willing to contemplate. The House of Commons would not have any formal say in the matter. The ‘Benn Act’s’ provisions would not apply if the Commons had already approved the motion approving the deal.

The EU (Withdrawal Agreement) Bill

In the absence of a “technical” extension, Parliament would have, as things stand, just eight sitting days including exit day to pass the EU (Withdrawal Agreement) Bill. This would involve both the Commons and the Lords passing a complex and wide-ranging constitutional statute at almost unprecedented speed. As of Friday 18 October this Bill has not yet been published in draft, although the May Government published a white paper in July 2018 explaining in high-level terms the approach the Bill was likely to take.

The Bill is expected to:

preserve the effect of major parts of the European Communities Act 1972 for the agreed transition or implementation period;

give the Withdrawal Agreement a special and ongoing status in UK law; and

confer significant delegated powers on the UK Government and devolved authorities in Scotland, Wales and Northern Ireland.

As with the EU (Withdrawal) Bill itself, the scope, breadth and limits on those powers are likely to attract considerable attention and present challenges for Parliament in terms of holding the Government to account.

Hasn’t Parliament legislated really quickly before?

Parliament debated the procedure and substance of the ‘Benn-Burt Bill’ across just four sitting days in September this year. This was only possible because a clear majority in both Houses wanted to pass the Bill quickly and, in the case of the Lords, the Government eventually agreed to facilitate the Bill’s passage rather than to obstruct it by “talking-out” the debate.

The EU (Withdrawal) Bill 2017-19, a Bill of more comparable complexity and kind, saw 12 sitting days’ debate in the Commons, 20 sitting days’ debate in the Lords, and a further four sitting days to settle disagreements over amendments, over the course of nine months. The European Union (Amendment) Act 2008 (which allowed the Lisbon Treaty to be ratified) had 13 sitting days’ debate in the Commons and 12 sitting days’ debate in the Lords, over the course of five months. If the Government is to facilitate the smooth passage of the EU (Withdrawal Agreement) Bill through both Houses, it will likely need to secure agreement on a cross-party basis for a legislative timetable (especially for the House of Lords).

About the author: Graeme Cowie is a Senior Library Clerk at the House of Commons Library, specialising in Brexit.

Image: ©UK Parliament/Jessica Taylor