¹ Theresa May, ‘The government's negotiating objectives for exiting the EU’ 17 January 2017, available at https://www.gov.uk/government/speeches/the-governments-negotiating-objectives-for-exiting-the-eu-pm-speech.

² See for example E Lydgate et al ‘The UK trade landscape after Brexit’ UK Trade Policy Observatory, October 2016; Holmes, R et al. ‘Negotiating the UK's post-Brexit trade arrangements’ (2016) 238(1) National Institute Economic Review R22–R3CrossRefGoogle Scholar; H Hestermeyer and F Ortino ‘Towards a UK trade policy post-Brexit: the beginning of a complex journey’, King's College London Law School Research Paper No 2017-04.

³ Memorandum of Understanding and Supplementary Agreements between the UK Government, the Scottish Ministers, the Welsh Ministers, and the Northern Ireland Executive Committee (October 2013), available at https://www.gov.uk/government/publications/devolution-memorandum-of-understanding-and-supplementary-agreement.

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⁸ Ibid, Art 3, Annex 2.

⁹ Regulation (EU) No 952/2013 of the European Parliament and of the Council of 9 October 2013 laying down the Union Customs Code OJ L 269, 10.10.2013.

¹⁰ Ibid, Art 6(2) Protocol.

¹¹ Commons votes to reject Government's EU Withdrawal Agreement, 29 March 2019 https://www.parliament.uk/business/news/2019/march/mps-debate-and-vote-on-the-withdrawal-agreement-with-the-european-union/.

¹² R Baldwin ‘21st century regionalism: filling the gap between 21st century trade and 20th century trade rules’, Staff Working Paper ERSD-2011-08, available at https://papers.ssrn.com/sol3/papers.cfm?abstract_id=1869845.

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¹⁵ For the EU's textual proposals released during the negotiation of the TTIP see http://ec.europa.eu/trade/policy/in-focus/ttip/index_en.htm.

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²⁵ For an analysis of the EU Withdrawal Bill and its impact on devolved competences see S Tierney ‘The European Union (Withdrawal) Bill: legal implications for devolution’ UCL The Constitution Unit, 2 September 2017, available at https://constitution-unit.com/2017/09/07/the-european-union-withdrawal-bill-legal-implications-for-devolution; Douglas-Scott, S ‘Short cuts’ (2017) 39(16) London Review of Books 16–17Google Scholar; N McEwen ‘Trust in a time of Brexit’ The UK in a Changing Europe, 28 November 2017, available at http://ukandeu.ac.uk/trust-in-a-time-of-brexit.

²⁶ The Good Friday Agreement (or Belfast Agreement) signed on 10 April 1998. Text available at https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/136652/agreement.pdf.

²⁷ A Gordon ‘Brexit and the Irish border: legal and political questions’ Royal Irish Academy – British Academy Brexit Policy Discussion Paper October 2017, available at https://www.britac.ac.uk/sites/default/files/BrexitandtheIrishBorderLegalandPoliticalQuestions_0.pdf.

²⁸ HM Government ‘Northern Ireland and Ireland’ Position Paper 16 August 2017; European Commission ‘Guiding principles transmitted to EU27 for the Dialogue on Ireland/Northern Ireland’ 6 September 2017; European Commission ‘Joint report from the negotiators of the European Union and the UK Government on progress during phase 1 of negotiations under Article 50 TEU on the UK's orderly withdrawal from the European Union’ 8 December 2017, text available at https://ec.europa.eu/commission/sites/beta-political/files/joint_report.pdf; https://ec.europa.eu/commission/sites/beta-political/files/guiding-principles-dialogue-ei-ni_en.pdf.

²⁹ Above n 27.

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³⁷ Ibid.

³⁸ HM Revenue and Customs ‘Regional trade in goods statistics’, 7 June 2018, p 19, available at https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/686571/RTS_Q4_2017.pdf.

³⁹ Ibid, pp 10–17.

⁴⁰ R Rawlings ‘Brexit and the territorial constitution’ The Constitution Society, November 2017, p 20, available at https://consoc.org.uk/publications/brexit-territorial-constitution-devolution-reregulation-inter-governmental-relations/.

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⁴⁵ ‘Scotland's place in Europe’ (2016) para 187, available at http://www.gov.scot/Resource/0051/00512073.pdf.

⁴⁶ ‘Scotland's role in the development of future UK trade arrangements – a discussion paper’, Scottish Government, August 2018, available at https://www.gov.scot/Resource/0053/00539758.pdf.

⁴⁷ Department for International Trade ‘Preparing for our future UK trade policy’ October 2017, available at https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/654714/Preparing_for_our_future_UK_trade_policy_Report_Web_Accessible.pdf at p 22.

⁴⁸ HM Government The UK's Exit from and New Partnership with the European Union Cm 9417, 2017, p 17.

⁴⁹ A Greer ‘Brexit and devolution’ (2017) The Political Quarterly 2.

⁵⁰ S Coates ‘Liam Fox tries to bypass Scots and Welsh in bid for Brexit trade deals’ The Times, 19 April 2017; ‘Brexit: trade deals need UK-wide consensus, Carwyn Jones says’ BBC, 19 August 2017, available at https://www.bbc.co.uk/news/uk-wales-politics-40985845.

⁵¹ Trade Bill 2017–19, 122-EN.

⁵² House of Commons, Public Bill Committee: 23 January 2018, 34.

⁵³ House of Commons, Notice of Amendments given up to and including Tuesday 30 January 2018, NC11.

⁵⁴ Trade Bill, Sch 1, para 1(1).

⁵⁵ Trade Bill, Sch 1, para 3(2) and (3).

⁵⁶ P Fafard and P Leblond ‘Twenty-first century trade agreements: challenges for Canadian federalism’ The Federal Idea, September 2012, p 13, available at https://ideefederale.ca/documents/challenges.pdf; M Gehring ‘Subnational participation in international trade law options for the European Union’ CIGI Papers No 167 – April 2018, available at https://www.cigionline.org/sites/default/files/documents/Paper%20no.167_web.pdf.

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⁷⁶ Uruguay Round Agreements Act, Pub L 103-465.

⁷⁷ 19 USC § 3512(b)(2)(A). Also note that a similar limitation is typically included in US FTAs (see Sheffler, S ‘A balancing ACT: state participation in free trade agreements with sub-central procurement obligations’ (2015) 44 Pub. Cont LJ 733Google Scholar.

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⁸⁰ Sheffler, above n 77, at 740–743.

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⁸⁸ Meyer, above n 81, at 270.

⁸⁹ German Constitution, Art 32(1).

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¹⁰² Hrbek, above n 97.

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¹⁰⁴ See section 2(b).

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¹⁰⁹ AG Canada v AG Ontario (Labour Conventions case) [1937] App Cas 326 (CAN PC).

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¹²⁴ Paquin, above n 116.

¹²⁵ The CPTPP is currently in the process of being ratified in Canada. The text of the agreement is available at http://www.international.gc.ca/trade-commerce/trade-agreements-accords-commerciaux/agr-acc/tpp-ptp/text-texte/toc-tdm.aspx?lang=eng.

¹²⁶ Freudlsperger, above n 82, at 1697.

¹²⁷ C Kukucha, ‘Provincial/territorial governments and the negotiation of international trade agreements’ (2016) 10 IRPP Insight 12, available at http://irpp.org/research-studies/insight-no10/.

¹²⁸ Freudlsperger, above n 82, at 1697.

¹²⁹ Kukucha, above n 84, at 225–226.

¹³⁰ Kukucha, above n 84, at 225.

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¹³⁶ Northern Ireland Act 1998, Sch 2.

¹³⁷ R (on the application of Miller) v Secretary of State for Exiting the European Union (Birnie and Others intervening) [2017] UKSC 5, [2017] 2 WLR 583, para 54.

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¹⁴⁰ Aust, above n 71, p 170.

¹⁴¹ P Bowers and C Sear ‘The Sewel convention’, House of Commons Briefing paper SN02084, 25 November 2005, available at https://researchbriefings.parliament.uk/ResearchBriefing/Summary/SN02084.

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¹⁴⁴ Ibid, para 148.

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¹⁴⁷ Northern Ireland Act 1998, ss 21 and 26; Scotland Act 1998, s 58; Government of Wales Act 2006, s 82.

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¹⁵¹ Ibid, pp 12–16.

¹⁵² Ibid, p 52.

¹⁵³ Ibid, p 53.

¹⁵⁴ Ibid, p 54.

¹⁵⁵ Ibid, p 55.

¹⁵⁶ Ibid, p 56.

¹⁵⁷ Ibid.

¹⁵⁸ Ibid.

¹⁵⁹ Ibid, p 57.

¹⁶⁰ Ibid.

¹⁶¹ House of Lords Select Committee on the Constitution ‘Inter-governmental relations in the UK’ 11^th Report of Session 2014–15, p 18, available at https://publications.parliament.uk/pa/ld201415/ldselect/ldconst/146/146.pdf.

¹⁶² Ibid, p 18.

¹⁶³ Ibid.

¹⁶⁴ Ibid, p 19.

¹⁶⁵ Ibid, p 14.

¹⁶⁶ Kenealy, D ‘Concordats and international relations: binding in honour only’ (2012) 221(1) Regional and Federal Studies 69Google Scholar.

¹⁶⁷ McEwen et al, above n 134.

¹⁶⁸ House of Lords Select Committee, above n 161; Scottish Parliament ‘Changing Relationships: Parliamentary Scrutiny of Intergovernmental Relations’, 8th Report, 2015, 6 October 2015.

¹⁶⁹ Ibid.

¹⁷⁰ O Ilott ‘Four uncomfortable truths about a quick deal on UK-US trade’, Institute for Government, 16 January 2017; M Busch et al ‘The future of US-UK trade – what case for a bilateral agreement? UKTPO Briefing Paper July 2018, p 6.

¹⁷¹ Kenealy, above n 166.

¹⁷² See section 2(b).

¹⁷³ Kukucha, above n 117.

¹⁷⁴ Omiunu, above n 18.

¹⁷⁵ See section 1(a).

¹⁷⁶ Paquin, above n 116, at 548.

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¹⁷⁸ Canada-EU CETA, Arts 21.1–21.9, [2016] OJ L 11, 23.

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¹⁸¹ Above n 125.

¹⁸² CPTPP, Art 25.6. See also Bollyky, T ‘Regulatory coherence in TPP talks’ in Lim, C et al. (eds) The Trans-Pacific Partnership (Cambridge University Press, 2012) p 171CrossRefGoogle Scholar; Gantz, D ‘The TPP and RCEP: mega-trade agreements for the Pacific rim’ (2016) 22 Arizona Journal of International and Comparative Law 57Google Scholar.

¹⁸³ See for example Royles, E ‘Small, smart, successful: a nation influencing the twenty-first-century world? The emerging Welsh paradiplomacy’ (2010) 23(1) Contemporary Wales 142Google Scholar; Ouimet, H Rioux ‘From sub-state nationalism to subnational competition states: the development and institutionalization of commercial paradiplomacy in Scotland and Quebec’ (2015) 25(2) Regional and Federal Studies 109CrossRefGoogle Scholar; Royles, E ‘Substate diplomacy, culture, and Wales: investigating a historical institutionalist approach’ (2016) 46(2) Publius 224CrossRefGoogle Scholar.

¹⁸⁴ Fafard and Leblond, above n 56, p 13.

¹⁸⁵ Henderson, A et al. ‘How Brexit was made in England’ (2017) 19(4) The British Journal of Politics and International Relations 631CrossRefGoogle Scholar.

¹⁸⁶ Greer, above n 49, at 4.

¹⁸⁷ Rawlings, above n 40, p 5.