Context: On 14 September, the First Ministers/leaders of Scotland, Wales and Northern Ireland, along with Sinn Féin’s Mary Lou McDonald, signed a Memorandum of Understanding (MoU) in Cardiff advocating greater self-determination and independence from the U.K.
- The MoU has significance because the three constituent nations have different constitutional objectives: Scottish independence, Welsh autonomy/possible independence, and Irish reunification for Northern Ireland.
U.K.: A Multi-National State
- The U.K. is commonly described as a multi-national state/State of Unions, comprising four constituent nations: England, Scotland, Wales and Northern Ireland.
- Scotland, Wales and Northern Ireland possess distinct cultural identities, languages, historical experiences and political institutions, contributing to long-standing demands for greater autonomy.
- The U.K. has therefore developed an asymmetric system of devolution, with different powers and arrangements applying to its constituent nations.
- The Cardiff MoU represents an attempt by political forces in three of these nations to collectively place their constitutional aspirations before Westminster.
Northern Ireland: Reunification with Ireland
Good Friday Agreement and Power Sharing
- Northern Ireland's political system is based on power-sharing/consociationalism under the Good Friday Agreement (1998), designed to accommodate the competing Nationalist/Republican and Unionist/Loyalist communities.
- The First Minister and Deputy First Minister are drawn from the largest parties representing the two largest political blocs, ensuring participation of both communities.
- Sinn Féin, the largest Nationalist party, currently leads the Northern Ireland Executive, with Michelle O'Neill serving as First Minister.
Constitutional Objective
- Unlike Scottish nationalists, Northern Irish Nationalists generally seek reunification with the Republic of Ireland, rather than an independent Northern Ireland.
- The Good Friday Agreement provides for the possibility of Northern Ireland joining a united Ireland through a referendum.
- A border poll can be called by the U.K. Secretary of State for Northern Ireland when the statutory conditions concerning the likelihood of majority support for reunification are met, subject to the rules governing the timing of referendums.
- Unionist leaders have rejected the Cardiff MoU as not representing Northern Ireland as a whole, arguing that it reflects the position of Sinn Féin rather than the power-sharing government collectively.
Scotland: Demand for Independence
- Scotland voted for devolution in 1997, leading to the establishment of the Scottish Parliament at Holyrood in 1999.
- The Scottish National Party (SNP) has made greater autonomy and independence a central political demand since becoming a major governing force in Scotland.
- In the 2014 independence referendum, the No campaign secured 55.3%, while the Yes campaign received 44.7%.
- The demand for another referendum gained renewed momentum after Brexit, particularly because 62% of Scottish voters had voted to remain in the EU in 2016, while the U.K. subsequently left the EU.
- According to the article, the May 2026 Scottish elections produced 73 pro-independence members in Holyrood when the SNP and Scottish Green Party are considered together.
- First Minister John Swinney has consequently renewed efforts for mechanisms that could enable another independence referendum by 2031.
Wales: Gradual Shift towards Greater Autonomy
- Wales has historically shown weaker support for independence than Scotland, but demands for greater devolution have gradually increased.
- Plaid Cymru, established in 1925, has long advocated Welsh self-determination.
- The 1997 devolution referendum narrowly supported the creation of a Welsh Assembly, with 50.3% voting in favour.
- In the 2011 referendum, approximately 63.49% voted in favour of expanding the legislative powers of the Welsh Assembly, compared with 36.51% against.
- The Labour Party has generally opposed full independence but has increasingly supported greater constitutional powers for Wales, including in areas such as policing and justice.
- In 2021, the Welsh Government established the Independent Commission on the Constitutional Future of Wales to examine options including independence, enhanced devolution and a more federal U.K.
- Its 2024 report noted that Welsh independence could no longer be excluded from public debate, while highlighting potential short- to medium-term challenges relating to currency, public finances, trade and cross-border movement.
- Rhun ap Iorwerth has adopted a more gradual position, ruling out an independence referendum during his current term while maintaining that the Welsh people should retain the option to determine their constitutional future.
Westminster's Response
- The U.K. Government has simultaneously pursued a broader agenda of decentralisation and devolution, including efforts to transfer powers away from central government in London.
- However, the Westminster government has opposed immediate moves towards constitutional referendums in both Northern Ireland and Scotland.
- On Irish unity, the Prime Minister has stated that a border poll is currently not on the government's agenda, prioritising issues such as the cost of living and public services.
- Sinn Féin has argued that the right to determine Northern Ireland's constitutional future is provided for under the Good Friday Agreement.
- Similarly, Westminster has rejected current calls for establishing a legal mechanism for a new Scottish independence referendum.
The EU Dimension
- The Cardiff MoU also calls for closer relations with, and eventual reintegration into, the European Union, reflecting dissatisfaction with the consequences of Brexit.
- In the 2016 Brexit referendum, Scotland (62%) and Northern Ireland (55%) voted to remain, whereas Wales voted approximately 52% to leave.
- Political leaders supporting the MoU argue that Brexit has increased non-tariff barriers, paperwork and trade-related delays despite the existence of the U.K.–EU Trade and Cooperation Agreement.
- However, leaving the U.K. would not automatically result in EU membership; a newly independent state would have to undergo the EU accession process.
- The accession experience of countries such as Montenegro and Serbia, which began negotiations in 2012 and 2014 respectively, illustrates that EU integration can be a lengthy process.
Key Constitutional Concepts
Devolution
- Devolution means transferring powers from the central government to sub-national governments while retaining the ultimate constitutional sovereignty of the central state.
- The U.K. has an asymmetric devolution model, with Scotland, Wales and Northern Ireland possessing different institutional arrangements and powers.
Independence vs Devolution
- Devolution: Greater self-government while remaining within the U.K.
- Independence: Separation from the U.K. and establishment of a sovereign state.
- Irish reunification: Northern Ireland becoming part of the Republic of Ireland, rather than becoming an independent state.
Good Friday Agreement, 1998
- Also known as the Belfast Agreement, it established the framework for peace and power-sharing in Northern Ireland.
- It recognises the principle that Northern Ireland's constitutional status should ultimately reflect the consent of its people.
- It established institutions based on power sharing between the principal political communities.
Significance of the Cardiff MoU
- The MoU is not a legally binding treaty; it is primarily a political statement by political parties/leaders from Scotland, Wales and Northern Ireland.
- Its importance lies in bringing together different constitutional movements around a broader demand for greater self-determination and reduced dependence on Westminster.
- At the same time, the three movements have distinct end goals: Scottish independence, Welsh autonomy/possible independence, and Irish reunification.
- The MoU also connects the constitutional question with Brexit, European integration, economic interests and regional governance.
- It therefore highlights the continuing tension between centralisation and devolution within the U.K.'s asymmetric constitutional framework.
