Martin McGuinness has acknowledged he underestimated the impact of Queen Elizabeth's historic State visit to Ireland, admitting the British monarch's conduct and symbolic gesture to those who fought for Irish freedom "exceeded expectations."

The Sinn Fein politician speaking ahead of a talk at the Kinsale Peace Process in Co. Cork yesterday, the former IRA commander, who has met the Queen on a number of occasions since, spoke of his relationship with the monarch.

He said: "The Queen's visit exceeded expectations. We didn't know in Sinn Fein what she was going to do, but neither did anyone in the country. But she showed such reverence when she bowed at the wreath-laying ceremony in the Garden of Remembrance in Dublin and then acknowledged the Irish language in her speech at Dublin Castle.

"I'm convinced she's a woman who totally understands the peace process and who wants to contribute to the peace process and I know that because I've met her on a number of occasions.

"She's a very positive force and she has showed she is prepared to engage in acts of reconciliation. She too was someone who suffered as a result of the conflict and she knows my history, yet both of us were prepared to rise above all of that."

McGuinness also likened his warm relationship with The Queen to the unlikely bond he forged with Ian Paisley during their time together in office.

He said he still misses both the old working relationship and the private company he enjoyed with Dr. Paisley, his once bitter enemy, who died in September 2014 following a long illness.

But he said the strong bond he developed during their time together in office has helped build up an enduring friendship with the former DUP leader's widow and her family.

Paisley – the once hard line unionist who had vowed never to share power with Sinn Fein – spent just over a year as First Minister of Northern Ireland from May 2007, working alongside Deputy First Minister McGuinness in a pivotal period in the peace process.

Images of the pair laughing and joking together during their time together in power famously earned them the nickname the 'Chuckle Brothers.'

The veteran Derry-born politician and former President of Ireland candidate, who is set to return to his Foyle constituency for May's Northern Ireland Assembly election, also stressed he remains as committed as ever to a united Ireland.

He added: "I'm a dedicated Irish republican and I want to see reunification by political means. There's certainly a strong economic case too for unity, but the only way it can happen is through peaceful and democratic means."

Sinn Fein was involved in street protests against the four-day visit in May 2011, the first by a British monarch in 100 years.

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