DERRY, NORTHERN IRELAND - JUNE 9: Sir John Major and Tony Blair speak as they walk across the Peace Bridge on June 9, 2016 in Derry, Northern Ireland. Former British Prime Ministers Sir John Major and Tony Blair travelled to Derry City in Northern Ireland warning that voting to leave the EU could "jeopardise the unity" of the UK. They suggested that it may cause Scotland to re-visit an independence referendum and put Northern Ireland's "future at risk". Both politicians were instrumental in bringing peace to the region. The Vote Leave campaign has said the idea that a Brexit could threaten the Northern Ireland Peace Process was irresponsible. (Photo by Jeff J Mitchell - WPA Pool/Getty Images)
