Following a stroke in 2012 the veteran politician had suffered ill health and passed away peacefully in his London home, his family said.He was 88 years old.Benn served as a Labour MP for over 50 years and was a cabinet minister in the governments of Harold Wilson and James Callaghan.He was regarded as one of the most prominent, influential and out-spoken members of the party.When he retired from his parliamentary seat in 2001, he was famously quoted as saying he wanted to "spend more time on politics".He was later elected president of the Stop the War Coalition and was a popular speaker at protests and festivals.During his career, he voiced support for Sinn Féin and had advocated for a united Ireland.Mr McGuinness described Mr Benn as a "dear friend and a wonderful politician".Sinn Féin President Gerry Adams added that he was "a true friend of the Irish people"."Tony was a champion of the downtrodden and of the voiceless in Britain, in Ireland and throughout the world."I met Tony many times over the years. He was a thoughtful and highly intelligent human being and a genuinely nice man, whom I will greatly miss."So sad.Our dear friend Tony Benn has died.He was a wonderful politician,a gentle soul,a peacemaker.The Irish People had no truer friend#RIP— Martin McGuinness (@M_McGuinness_SF) March 14, 2014Foyle SDLP MP Mark Durkan described Benn as "a great parliamentarian, wonderful platform orator, and both personable and impressive in private conversation"."He was a man who just naturally radiated charm, warmth and honour," he said.David Begg, General Secretary of the Irish Congress of Trade Unions, the umbrella organisation for trade unions in Northern Ireland, said: "Tony Benn was the outstanding political figure of his age and, indeed, one of the brightest stars of the wider labour movement."He was a giant of his generation."Meanwhile the Irish Minister for Foreign Affairs and Tánaiste Eamon Gilmore said Benn "devoted 60 years to a career in the service of others and was a man of great integrity and determination".