A campaigner is going to the High Court in England to challenge the Government over gender-neutral passports.
Christie Elan-Cane believes the UK's passport application process, which requires individuals to indicate whether they are male or female, is "inherently discriminatory".
Elan-Cane, who has campaigned for more than 25 years to achieve legal and social recognition for non-gendered identity, sees the issue of "X" (for unspecified) passports as a key focal point of the non-gendered campaign.
A two-day judicial review, which begins in London today, challenges the lawfulness of the policy administered by Her Majesty's Passport Office.
It will be argued in an action brought against the British Home Secretary that the policy is "inherently discriminatory and part of a wider systemic failure to address the needs of individuals whose identities are neither male nor female".
At a previous High Court hearing - when a judge ruled that the case was "arguable" and should proceed to a full airing - Kate Gallafent QC, for Elan-Cane, said: "The claimant's identity is that of a non-gendered person: someone who does not identify as either male or female.
"The claimant considers that obtaining and using a passport currently involves the claimant making a false declaration as to the nature of the claimant's gender identity, which causes the claimant considerable distress."
She said the impact of the passport office's "refusal to provide for X passports affects not only non-gendered persons such as the claimant but a broad section of the public".
Those affected included intersex people, who are born with biological characteristics of both sexes and "who often identify as both or neither male or female", transgendered people and individuals with gender dysphoria.
The QC said:
Elan-Cane said in a statement: "Legitimate identity is a fundamental human right, but non-gendered people are often treated as though we have no rights.
"The UK's passport application process requires applicants to declare whether they are male or female.
"It is inappropriate and wrong that someone who defines as neither should be forced to make that declaration."