Hampstead Heath Ladies’ Pond is facing legal action for allegedly failing to ban transgender women despite the landmark Supreme Court gender ruling.

The famed women-only bathing spot has maintained its trans-inclusive policy pending a ‘review’ in spite of the UK’s highest court ruling in April that trans women are not legally female.

Women’s rights campaigners sent a legal letter to the City of London Corporation, which manages the ponds, last week warning they intend to bring a legal challenge unless the policy is revoked with 'immediate effect’.

The Kenwood Ladies' Pond opened in 1925 and is the sole women-only freshwater swimming pool in the country. There is also a men-only pond and a mixed-sex pond.

The legal letter, seen by the Mail, says that the current policy ‘violates the dignity of women using the Ladies’ Pond’ and that the Corporation is ‘operating it unlawfully by allowing trans identifying males to access it’.