The agreement was negotiated as a step towards easing long-standing tensions between Britain and Ireland over Northern Ireland, although trade unionists in Northern Ireland (who were in favour of the UK`s continued existence) strongly opposed their southern neighbour having a say on domestic policy issues. Many political leaders – including Thatcher, who had been strongly committed to British sovereignty in Northern Ireland – were convinced that a solution to years of religious violence in Northern Ireland could only be found through a comprehensive agreement. By-elections called after the resignation of the Unionists did not give voters a clear choice because of the reluctance of other parties to challenge them. No Unionist candidate rejected another, while the SDLP and Sinn Féin ran for only the four seats, where the majority of votes for nationalist candidates had been voted on in previous elections. The SDLP has rejected an offer by Sinn Féin to enter into a nationalist electoral pact against the Unionist electoral pact.  The SDLP was given the seat of Newry and Armagh. The alliance has formally committed to fighting all seats on a platform to support the agreement, but some local branches have refused to choose candidates. The Workers` Party sat on a few seats. In four constituencies where no party would oppose the Unionist MP, a certain Wesley Robert Williamson changed his name by a poll in «Peter Barry» (the name of the Irish Minister of Foreign Affairs) and appeared on the label «For the Anglo-Irish Agreement», but did not campaign. Despite this, he received nearly 7,000 votes and saved three deposits. The Unionist parties between them won more than 400,000 votes and more than 71% of the overall survey, but as there were no by-elections in the stubborn nationalist seats of West Belfast and Foyle, this figure is distorted. [Citation required] The agreement was adopted by Seanad Iireann by 88 votes to 75 and by 37 votes to 16.
  The Irish nationalist Fianna Féil party, the main opposition party in Ireland, also rejected the agreement. Fianna-Fiil leader Charles Haughey said the agreement was contrary to Articles 2 and 3 of the Irish Constitution because it had officially recognised British jurisdiction in Northern Ireland. He was also rejected by independent Republican TDs Neil Blaney and Tony Gregory, as a «con job» agreement. Despite this opposition, all the other major parties of the Republic supported the agreement ratified by the Oireachtas. Anglo-Irish Agreement signed by Margaret Thatcher and Garret FitzGerald, Irish Prime Minister, on 15 November 1985 at Hillsborough Castle in County Down, N.Ire, which brought the Irish government a formal advisory role in the affairs of Northern Ireland. The agreement is considered one of the most important developments in Anglo-Irish relations since the creation of the Irish Free State in 1922 and provided for regular meetings between Irish and British government ministers on Northern Ireland issues.