Britain's most senior Roman Catholic cleric says he believes priests should be able to marry if they wish to do so.

Scottish Catholic leader Cardinal Keith O'Brien, who will help elect the next Pope, told the BBC on Friday it was clear many priests struggled to cope with celibacy, and they should be free to marry and have children if they so desire.

Made a cardinal by the late Pope John Paul II 10 years ago, the 74-year-old O'Brien will be part of the conclave that chooses the next Pope.

Only the third cardinal since the Reformation to be made a cardinal, he spoke of his surprise at the resignation of Benedict XVI, who will step down on Feb. 28.

O'Brien said he was open to the new pope coming from outside of Europe.

In his interview with BBC Scotland, O'Brien said some issues such as abortion and euthanasia are "basic dogmatic beliefs" of "divine origin" which the Church could never accept.

But Cardinal O'Brien, who is the Archbishop of St. Andrews and Edinburgh, said it would be within the scope of the new pope to consider whether the Catholic Church should change its stance on other issues, which were not of divine origin.

"For example the celibacy of the clergy, whether priests should marry - Jesus didn't say that.

"There was a time when priests got married, and of course we know at the present time in some branches of the church - in some branches of the Catholic church - priests can get married, so that is obviously not of divine of origin and it could get discussed again."

The rule of celibacy is not a Catholic doctrine and could be changed by the next pope. There are some married priests in the church, such as those who have converted from Anglicism, not bound by the rules of celibacy.

Like many Scottish Catholics, O'Brien has Irish roots. He was born in Ballycastle, Co. Antrim, in 1938 on St Patrick's Day, but as a young child moved with his family to Scotland, where his father served with Britain's Royal Navy.

He noted, "In my time there was no choice and you didn't really consider it too much, it was part of being a priest. When I was a young boy, the priest didn't get married and that was it.

"I would be very happy if others had the opportunity of considering whether or not they could or should get married.

"It is a free world and I realise that many priests have found it very difficult to cope with celibacy as they lived out their priesthood and felt the need of a companion, of a woman, to whom they could get married and raise a family of their own."

It was not the first time Cardinal O'Brien had spoken of his view that the church would one day accept married priests. In 2005, he told the Catholic Times: "Having seen something of the apostolate of married deacons, I can foresee the day when there will be married priests."

He is however, adamant in stating the church opposition to same-sex marriage.

But, he acquired a reputation as a liberal Catholic prior to becoming a cardinal. In 2002, he said he said he would have 'no problems with celibacy withering away," adding: "There is no great theological argument against celibacy ending, nor any theological problem with it ending at all."