Prince Philip 'at ease' before Martin McGuinness meeting

The Queen shakes hands with Peter Sheridan from Co-operation Ireland as Prince Philip meets Northern Ireland Deputy First Minister Martin McGuinness at the Lyric Theatre in Belfast in 2012

Prince Philip was at ease and "displayed his sense of humour" ahead of a meeting with Martin McGuinness, the head of a peace charity has said.

Peter Sheridan, chief executive of Co-operation Ireland, said he met the Duke of Edinburgh in 2012.

The Duke of Edinburgh and the Queen met the then-Sinn Féin deputy first minister at an event in the Lyric Theatre in Belfast.

Mr McGuinness had been senior commander in the Provisional IRA.

The meeting was symbolic as the IRA murdered the Queen's cousin, Lord Louis Mountbatten, in the Republic of Ireland in 1979.

The IRA detonated a bomb on his family's fishing boat in the harbour of Mullaghmore, in the north west Ireland.

• Who was Lord Mountbatten?

'Sense of humour'

Speaking to BBC News NI, Mr Sheridan said he had shown the Duke portraits of victims of the Troubles by artists Colin Davidson.

"I was fortunate to be able to walk him around," he said.

"And despite what the event was going to be about, he had that sense of humour that he displayed on that day.

• NI books of condolence opened for Prince Philip

• Prince Philip's 73-year association with NI

• Northern Ireland pays tribute to Prince Philip

• In Pictures: Prince Philip in Northern Ireland

"He certainly put a lot of people at ease, despite the enormity that was about to happen a few minutes later."

'Taken aback by it'

Tributes have been paid to the Duke of Edinburgh across Northern Ireland and the Republic of Ireland following his death.

Mary McAleese said the Duke had lived "a very long and remarkable life"

The Stormont Assembly sit on Monday to allow MLAs to pay tribute to Prince Philip, before suspending for the rest of the day.

Mary McAleese, a former President of Ireland, said he had lived "a very long and remarkable life, to lose him just shy of his 100th birthday, it's just desperately sad".

She also spoke about the Duke of Edinburgh's awareness of the political situation in Northern Ireland.

"I met him for the first time in 1995, two years before I became president," she said.

"I was fortunate to be asked to a small gathering around a lunch table in Buckingham Palace to talk about Northern Ireland.

Prince Philip at Hillsborough Castle during his last official visit to Northern Ireland in 2017

"The first thing that struck me was just how very, very well read both of them were. He was very interested in Irish politics and Irish history.

"He was very well read on history, but also very up to date on contemporary politics.

"He was very distressed, as they both were, by events in Northern Ireland, by sectarianism.

"That was new to me, and I was actually very taken by it."

Writing on social media on Friday evening, Northern Ireland actor Ian Beattie, who appeared in Game of Thrones, recalled meeting the Duke of Edinburgh, who he said was 86 at the time.

"He was charming, funny and spoke to everyone in the room. Over 100 people," he said.