Swedish prosecutors suspect Anna Lindstedt of organising a meeting in January between Gui’s daughter, China's ambassador and two businessmen about the possible release of her father, a dissident bookseller who is current imprisoned.
"He discovered at last that she had outgrown his liking. She had borne ten children and had lost many of her good looks, was growing old, in fact," a recently-unearthed letter revealed.
The apology comes more than 70 years after the letter was rejected.
Yann Moix, an award-winning French author made the comments in an interview with Marie Claire magazine.
Israeli author Amos Oz has died of cancer at the age of 79.