Martin McGuinness will attend a number of events during next week's state visit by President Higgins to the UK Martin McGuinness will attend a banquet hosted by the Queen during next week's state visit to Britain by Irish President Michael D Higgins. Sinn Féin president Gerry Adams said the decision had to be viewed against the backdrop of huge political change in recent years.
President Higgins will be joined by his wife, Sabina, and the Irish prime minister, Enda Kenny.
The visit, the first by an Irish head of state, begins on 8 April.
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Martina Purdy BBC News NI Political Correspondent As a youth, Martin McGuinness wore the uniform of an IRA volunteer - secretly, illegally and defiantly. Now, decades later, he will don a white tie and tails and publicly, cheerfully and - perhaps -still defiantly, attend the Queen's banquet at Windsor Castle.
We should not be too surprised. His journey has already seen him shake the hand of the Queen.
Not to attend the first state visit of an Irish president would undermine all his promises, made as an Irish presidential candidate, that he would work for peace.
It will put him in the company of Ireland's most senior figure, Michael D Higgins, and the presidency is a post that Sinn Féin covets.
It will also win praise in Dublin and the Republic, helping to reverse the political blunder of Sinn Féin's refusal to attend the Queen's visit to the Irish presidential residence in 2011.
And whatever votes Sinn Féin loses in Northern Ireland, if any, will be offset by potential gains in the south of Ireland.
Having conquered Northern Ireland, it is to the south that Sinn Féin's hungry eyes look for growth.
This decision is good for Martin McGuinness, peace and for Sinn Féin.
Martin McGuinness, who is Northern Ireland's deputy first minister and a former IRA commander, refused to sit in the House of Commons - when he was an MP - because he would have had to swear an oath of allegiance to the monarch.He shook hands with the Queen, both in private and in public, during her visit to Northern Ireland in 2012.
The move was regarded as a symbolic moment for the Northern Ireland peace process.
It was seen by many as one of the most significant of her reign as the IRA paramilitary group murdered the Queen's cousin, Lord Mountbatten, while he was on holiday in the Republic of Ireland in 1979.
During his visit, President Higgins will address both Houses of Parliament, another first for an Irish head of state.
The Queen will stage a traditional state banquet in honour of her guest at Windsor Castle, Mr Higgins and his wife will visit the Royal Shakespeare Company in Stratford-upon-Avon and he will attend another major dinner at the Guildhall in the City of London given by the Lord Mayor.
During the visit, the Queen will host a reception for leading figures from Northern Ireland's cultural, political and business life.
The visit by President Higgins follows on from the Queen and Duke of Edinburgh, who went in May 2011 to Ireland.