The Christian Legal Centre has warned Westminster City Council and the Crown Estate that it may take legal action if trans-inclusive Progress Pride flags are flown along Regent Street during Pride Month.

The warning comes as Westminster Council, in collaboration with the Crown Estate, plans to display the flags from mid-June to mid-July in celebration of the LGBTQ+ community.

Andrea Williams, chief executive of the Christian Legal Centre, called the move: “an attack on traditional beliefs about sex and gender”.

She told The Telegraph: “They send the message that people holding these views, which are worthy of respect in a democratic society, are not welcome.”

The Progress Pride flag, designed by Daniel Quasar, includes additional stripes to represent people of colour, the trans community and those living with HIV/AIDS.

Vicky Lee, founder of the LGBTQ+ venue Way Out Club, said: “Pride Month is here and the superheroes [trans community] are not going away anytime soon.”

A Westminster City Council spokesperson responded: “Pride is an annual and established fixture and has been supported by the council for many years... celebrations have a fixed duration and are both proportionate and fitting.”