Alexander "Derry" Irvine fell in love with the future Scottish secretary's wife, Alison, 27 years ago.

While Lord Irvine and Alison have since stayed together, Mr Dewar has never re-married and is described as not having recovered from the betrayal.

Donald Dewar: Has never remarried since his divorce

But the lord chancellor denies the story that the two men only spoke again for the first time at former Labour leader John Smith's funeral.

He insists they stayed on speaking terms for the sake of Mr Dewar's two children from his marriage.

Lord Irvine told The Sun newspaper: "I did feel guilty, but what happened to us is not all that unusual.

"But of course, if a marriage breaks down with someone who is not at fault, you would be a very unthinking person if you didn't feel a strong sense of guilt.

"Time is a great healer and Alison and I have had a very happy marriage. We have many interests in common."

The two men spoke publicly for the first time at John Smith's funeral

Lord Irvine also played down speculation over why he had chosen to omit any mention of his first wife from his entry in Who's Who.

He told The Sun: "My Who's Who entry was made six years after my divorce and I was looking forward not backwards."

Lord Irvine married Margaret Veitch in 1962 when he was 22 and she was 23.

After divorcing the future lord chancellor, she moved to Canada in 1976, where she reportedly lives alone in a hamlet near Toronto.

She was recently quoted as saying: "I haven't spoken to my ex-husband since I left Britain.