A publication devoted to the British monarchy has conceded that the murder of Lord Louis Mountbatten by the IRA played a key role in helping to bring the Troubles to an end.

Lord Mountbatten, a cousin of Queen Elizabeth, was killed during a family holiday when republican terrorists blew up his boat off the coast of Mullaghmore, Co Sligo, in August 1979, during the height of the Troubles.

The attack not only claimed the life of the 79-year-old aristocrat, but also the lives of two teenage boys and generated worldwide condemnation. On the same day as the murder the IRA ambushed and killed 18 British soldier is in the North.

In its profile of Lord Mountbatten, Royal Life magazine says that part of the legacy of the murder was that it helped to persuade hardliners to begin to seek a diplomatic resolution to the conflict in the North.

"Ironically, Louis's murder, widely viewed as a cowardly and despicable act at the time, may actually have helped the peace process in Northern Ireland, alienating some who had supported violence and persuading them to back diplomacy instead,” says the royalist publication, according to the Irish Independent.

The magazine also recalls that Prince Charles, who used to call Mountbatten his ‘Honorary Grandfather,’ broke his silence on the tragedy years later when he spoke to relatives of 9/11 victims at a service commemorating the 10th anniversary of the terrorist attack.

Referring to the murder of his “greatly loved great uncle,” Prince Charles said: "At the time I remember feeling intense anger, even hatred of those who could even contemplate doing such a thing.

"But then I began to reflect that all the greatest wisdom that has come down to us over the ages speaks of the overriding need to break the law of cause and effect, and somehow to find the strength to search for a more positive way of overcoming the evil in men's hearts."

When Queen Elizabeth visited the North in July 2012, Martin McGuinness addressed the killing of Mountbatten when he shook hands with the queen.

The former IRA commander said, "I said to the Queen and the Duke they too had lost a loved one."