Devolved national administrations

Main articles: Northern Ireland Executive, Scottish Government, and Welsh Government

The Scottish Parliament Building inHolyrood is the seat of the Scottish Parliament

Scotland, Wales and Northern Ireland each have their own government or executive, led by a First Minister, and a devolved unicameral legislature. England, the largest country of the United Kingdom, has no devolved executive or legislature and is administered and legislated for directly by the UK government and parliament on all issues. This situation has given rise to the so-called West Lothian question which concerns the fact that MPs from Scotland, Wales and Northern Ireland can vote, sometimes decisively, on matters affecting England that are handled by devolved legislatures for their own constituencies.

The Scottish Government and Parliament have wide ranging powers over any matter that has not been specifically 'reserved' to the UK parliament, includingeducation, healthcare, Scots law and local government. Following its victory at the 2007 elections the pro-independence Scottish National Party (SNP) formed a minority government with its leader, Alex Salmond, becoming First Minister of Scotland. The pro-union parties responded to the electoral success of the SNP by creating a Commission on Scottish Devolution which reported in 2009 and recommended that additional powers should be devolved, including control of half the income tax raised in Scotland. At the 2011 elections the SNP won re-election and achieved an overall majority in the Scottish parliament.

The Welsh Government and the National Assembly for Wales have more limited powers than those devolved to Scotland. Following the passing of theGovernment of Wales Act 2006 the assembly was able to legislate in devolved areas through Assembly Measures once permission to legislate on that specific matter had been granted by Westminster through a Legislative Competence Order; but since May 2011 the Assembly has been able to legislate on devolved matters through Acts of the Assembly, which require no prior consent. The current Welsh Government was formed after the 2011 elections, and is a minority Labour administration lead by Carwyn Jones, who had been First Minister of a Labour/Plaid Cymru administration since December 2009.

The Northern Ireland Executive and Assembly have powers closer to those already devolved to Scotland. The Northern Ireland Executive is led by a diarchy representing unionist and nationalistmembers of the Assembly. Currently, Peter Robinson (Democratic Unionist Party) and Martin McGuinness (Sinn Féin) are First Minister and deputy First Minister respectively.

Devolution in Northern Ireland is subject to the terms of the Good Friday Agreement and the subsequent British-Irish Agreement between the United Kingdom and the Republic of Ireland. Under those agreements, the participation of members of the Northern Ireland Executive in the North/South Ministerial Council, and co-operation between Northern Ireland and the Republic of Ireland on a number of devolved policy areas, are prerequisites of devolution in Northern Ireland. The British-Irish Intergovernmental Conference was also established under the agreements, whereby "the Irish Government may put forward views and proposals" on non-devolved matters with respect to Northern Ireland. However, the United Kingdom government remains sovereign over Northern Ireland unless a majority of the people of Northern Ireland vote to form a united Ireland.

The United Kingdom does not have a codified constitution and constitutional matters are not among the powers devolved to Scotland, Wales or Northern Ireland. Under the doctrine of Parliamentary sovereignty, the UK Parliament could, in theory, therefore, abolish the Scottish Parliament, Welsh Assembly or Northern Ireland Assembly. Indeed, in 1972, the UK Parliament unilaterally prorogued the Parliament of Northern Ireland, setting a precedent relevant to contemporary devolved institutions. In practice, the circumstances in which the UK Parliament would abolish devolution given the political constraints created by referendum decisions are unclear. The political constraints placed upon the UK Parliament's power to interfere with devolution in Northern Ireland are greater than in relation to Scotland and Wales, given that devolution in Northern Ireland rests upon an international agreement with the Government of Ireland.