In June 1940, to encourage the neutral Irish state to join with the Allies, British Prime Minister Winston Churchill indicated to the Taoiseach Éamon de Valera that the United Kingdom would push for Irish unity, but believing that Churchill could not deliver, de Valera declined the offer [REF].
The Ireland Act 1949 gave the first legal guarantee that the region would not cease to be part of the United Kingdom without the consent of the Parliament of Northern Ireland.