In the wake of former Prime Minister Margaret Thatcher’s death, Britain's former Northern Ireland secretary Peter Mandelson said the only thing Thatcher ever told him was that the Irish were “all liars” and not to be trusted.

However, Thatcher’s biographer Charles Moore is now saying that Thatcher was perhaps already in the grips of dementia when those comments were made, and that she did not intend them to be serious.

Speaking to the Irish Times, Moore said “In one sense, I wouldn’t take the story very seriously. I don’t mean it is not true, but what I mean is that you have to distinguish very strongly between the Margaret Thatcher in retirement and the Margaret Thatcher in office.”

“The one in office was the more genuine because in old age she was more disinhibited and just tending to fire off things,” Moore said.

Moore went on to say that Thatcher, like many of her generation, were inclined to mutter “‘Typical Irish’, that sort of thing.”

“Her dip was already beginning then,” said Moore of Thatcher when the alleged comments were made to Mandelson. “Because she had run things for so long she was still firing on all cylinders.”

“She was a bit like a car that is not in gear. You press the accelerator, it makes a great noise but it doesn’t go anywhere. She was slightly playing to the gallery: there was an element of humor in all this,” he said.

Moore went on to say that Thatcher’s comment are typical and in-line with other politicians. “Masses of political leaders do this sort of thing in private, ‘Oh, the bloody French, they are a nightmare.’ I am sure people say that all over the world about the British. It means something, but I don’t think it should be over-interpreted.”

“She did not hate the Irish,” says Moore, “she hated the terrorists.”

Moore also shed light on what he perceived Thatcher’s relationship with former Taoiseachs of Ireland Charles Haughey and Garret FitzGerald to be.

“She didn’t trust Haughey, in which I think she was not alone. She did basically trust FitzGerald. She is not very nice about [Garret] FitzGerald in her memoirs, but she did essentially respect him and even like him,” said Moore.

“She didn’t feel that these were a whole load of lying, thieving Paddies. [Her husband] Denis was rather more of that attitude. She thought that there was something to be done, and she liked some of the people,” added Moore.

Moore added that he believed Thatcher to be an imperialist in many ways, but that she was not so with Ireland, saying she thought it to be “entirely sensible” that the Republic of Ireland existed.

According to Moore, Thatcher did, however, feel “strongly that Northern Ireland was British because its people wanted it to be, rather like the Falklands.”

Former British Prime Minister Margaret ThatcherTim Graham