The following section of the April 1998 Good Friday Agreement, titled “Constitutional issues”, sets down principles for the government of Northern Ireland and the relationship between Britain, Northern Ireland and the Republic of Ireland:
The participants… will:
1. Recognise the legitimacy of whatever choice is freely exercised by a majority of the people of Northern Ireland with regard to its status, whether they prefer to continue to support the Union with Great Britain or a sovereign united Ireland;
2. Recognise that it is for the people of the island of Ireland alone, by agreement between the two parts respectively and without external impediment, to exercise their right of self-determination on the basis of consent, freely and concurrently given, North and South, to bring about a united Ireland, if that is their wish, accepting that this right must be achieved and exercised with and subject to the agreement and consent of a majority of the people of Northern Ireland;
3. Acknowledge that while a substantial section of the people in Northern Ireland share the legitimate wish of a majority of the people of the island of Ireland for a united Ireland, the present wish of a majority of the people of Northern Ireland, freely exercised and legitimate, is to maintain the Union and accordingly, that Northern Ireland’s status as part of the United Kingdom reflects and relies upon that wish; and that it would be wrong to make any change in the status of Northern Ireland save with the consent of a majority of its people;
4. Affirm that if in the future, the people of the island of Ireland exercise their right of self-determination on the basis set out in sections 1 and 2 above to bring about a united Ireland, it will be a binding obligation on both Governments to introduce and support in their respective Parliaments legislation to give effect to that wish;
5. Affirm that whatever choice is freely exercised by a majority of the people of Northern Ireland, the power of the sovereign government with jurisdiction there shall be exercised with rigorous impartiality on behalf of all the people in the diversity of their identities and traditions and shall be founded on the principles of full respect for, and equality of, civil, political, social and cultural rights, of freedom from discrimination for all citizens, and of parity of esteem and of just and equal treatment for the identity, ethos and aspirations of both communities;
6. Recognise the birthright of all the people of Northern Ireland to identify themselves and be accepted as Irish or British, or both, as they may so choose, and accordingly confirm that their right to hold both British and Irish citizenship is accepted by both Governments and would not be affected by any future change in the status of Northern Ireland.