The Queen’s visit to Ireland last year marked a ‘huge turning point’ in her life according to her grandson Prince William.

The claim is made in a new three-part BBC documentary, 'Diamond Queen,' to be aired on Monday nights.

The programme, to celebrate the British Monarch’s 60th year in power, details the relationship between Queen Elizabeth and Ireland.

Prince William talks at length in the documentary about the effect of last year’s Irish visit on the English Queen.

“The political tensions that stopped her travelling to Ireland left her like a child not allowed to go into a certain room,” claims Prince William.

“Last year’s visit to Ireland marked a huge turning point for her and bolstered the relationship between London and Dublin forged during the peace process.

“Until that point Ireland had always been off limits for my grandmother.

“It’s like a door that’s been locked to her for a long time and she’s been dying to see what’s on the other side of it.

“Many people won’t understand not being able to go somewhere or see something for your life and being almost like a child not allowed to go into a certain room.
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“She’d always wanted to go in an official capacity so I think it was a huge turning point for her.”

The second episode of the programme, to be aired next week, features Irish and British Prime Ministers Enda Kenny and David Cameron according to the Irish Independent.

Conservative Party leader Cameron applauds the Queen for travelling to Ireland as soon as she was able, despite his own apprehensions.

He says: “I was nervous about it but I was hugely admiring of the fact that the royal family wanted to go ahead with this visit relatively quickly after the finalising of the last bits of devolution of power to Northern Ireland.

“They didn’t want to wait and I thought that was a fantastic judgment.”

The programme will also feature interviews with Timothy Knatchbull and his mother, Countess Mountbatten of Burma, two of the survivors of the 1979 IRA bomb in Co Sligo, which killed the queen’s cousin, Lord Mountbatten.