HONG KONG, Feb 6 (Reuters) - Hong Kong's top court on Monday ruled that the policy of barring transgender people from changing their gender shown on ID cards unless they undergo full sex reassignment surgery violates their rights and is unconstitutional.

The Court of Final Appeal unanimously sided with appeals launched by transgender activists Henry Tse and another appellant identified as “Q” and quashed the Commissioner of Registration’s decision to refuse their applications to change their gender on their Hong Kong Identity Cards.

“The policy’s consequence is to place persons like the appellants in the dilemma of having to choose whether to suffer regular violations of their privacy rights or to undergo highly invasive and medically unnecessary surgery, infringing their right to bodily integrity,” the judges wrote in their judgment.

“Clearly this does not reflect a reasonable balance. The Policy imposes an unacceptably harsh burden on the individuals concerned.”

Both Tse and Q underwent lengthy medical and surgical treatments, including hormonal treatment and removal of breasts, but the registrar still required them to conduct a full sex reassignment surgery, which the pair argued was unnecessary, unwanted and highly invasive.

Tse welcomed the judgment as it would solve the “burning issues” he encountered due to possessing a wrong ID and he called for a gender recognition law.

“Today’s result is delayed justice, a Pyrrhic victory. This very case should never have happened,” Tse said in a statement.

"I will continue to work hard to plant the seeds for the transgender rights movement with my partners at Transgender Equality Hong Kong. I believe that one day, we shall succeed and welcome the rainbow with open arms."

The former British colony of Hong Kong returned to Chinese rule in 1997 under a "one country, two systems" formula meant to guarantee its freedoms and independent legal system for 50 years.

Many residents accuse Communist Party rulers in Beijing of creeping interference in the city's affairs, an accusation China denies.