A trans man in Hong Kong has launched a legal challenge against a new law that would ban him from marrying unless he undergoes surgery.

The man, known only as Q, told the South China Morning Post that he should not have to give up his “constitutional right” to marry his female partner if he refuses to have gender confirmation surgery.

The Court of Final Appeal ruled last year that the city should adopt guidelines for allowing trans people to marry, and set the government a July deadline to recognise such marriages.

However, the Security Bureau claims that the ruling “did not decide on the question of whether other transgenders or transsexuals who have not received [surgery] may also qualify to marry in their preferred sex.”

Surgery for trans men can often be dangerous, risky, costly and invasive.

Lawyer Michael Vidler says Q will launch a constitutional challenge if the law passes.

He said: “What would all the men of this world say if they were told they had to undergo full adult male circumcision before they were allowed to marry?

“Well, what they’re asking of Q is a thousand times worse than that.”

Vidler said the provision had gone ahead out of a mistaken attempt to stop same-sex marriage, which it equates with the issue of gender reassignment.

He said: “They constantly equate the two, even though the courts have clearly separated the two issues.”

The Australian state of Victoria recently invalidated the marriage of a trans man, because some of his documents did not recognise his gender.

The British Consulate in Hong Kong is banned from conducting same-sex marriage ceremonies, despite the British Consulate in China permitting them.