Trade union bosses have been hit by a furious backlash at their annual conference after telling transgender women they must use men’s toilets.

Leaders of the Public and Commercial Services union (PCS) had previously claimed the equality watchdog’s guidance in the light of the Supreme Court ruling on single-sex services was ‘not fit for purpose’ and ‘damaging’.

They had promised just last month to support ‘trans and non-binary members [who] will be facing worry and uncertainty following the judgement’.

But on the eve of the PCS’s annual conference in Brighton this week, the same union bosses warned delegates they risk breaking the law if they do not use the correct lavatories.

They acknowledged the ‘strength of feeling’ generated by the judgment - which declared that the definition of a woman is down to biological sex rather than gender identity - but added they had a ‘duty to act in accordance’ with equality law.