In lesbian partnerships, mutual breastfeeding has been regarded as a familiar expression of affection and tenderness.

Huhne, whilst married, had an affair with Trimingham, who herself was in a lesbian civil partnership and then later left his wife Vicky Pryce for Trimingham.

The pair were a long-established lesbian partnership who met as undergraduates at St Anne's College, Oxford in 1963.

The Energy Secretary left Miss Pryce for Carina Trimingham, an aide who was previously in a lesbian civil partnership.

The Star Tribune of Minneapolis broke new ground for metropolitan newspapers today when it published two announcements of lesbian "domestic partnerships" on what had traditionally been its wedding and engagement page.