The British woman, who requested to be identified only as QT in court, sued the director of immigration in 2014 after she was denied a spousal visa that would have granted her resident status and allowed her to work without the need for a separate visa.

The woman and her partner, a dual British and South African national identified only as SS and who was offered work in Hong Kong, had entered into a civil partnership in Britain. QT did not appear in court.

"Although I cannot be with you in person today, that does not diminish the joy I feel, knowing that Hong Kong's highest court has upheld my right, as a lesbian woman, to be treated equally by the Hong Kong government," QT said in a statement.

The unanimous ruling by five judges, upholding a lower court's decision, brings to an end the case involving rights for the lesbian, gay, bisexual and transgender (LGBT) community, which won support from more than 30 global banks and law firms, including Goldman Sachs and Morgan Stanley.

"This ruling strengthens Hong Kong's ability to attract

global talent and its competitiveness as Asia's pre-eminent global center for commerce," the companies said in a statement.

The decision effectively recognizes the rights of same-sex couples who legally entered civil partnerships abroad, said the British woman's lawyer, Michael Vidler.

"This does, and will, and can apply to a greater sphere," he said outside the Court of Final Appeal. "We never argued this case is about same-sex marriage for Hong Kong, but we hope this case will pave the way for exactly that."

ONE COUNTRY, TWO SYSTEMS

Hong Kong is a popular destination for expatriates, many of whom work in the city's financial services and legal sectors.

Homosexuality was decriminalised in Hong Kong 1991, although marriage is legally defined as a monogamous union between a man and a woman. It does not recognize same-sex marriage.

There is no law against sexual discrimination in the territory which is governed under a "one country, two systems" formula that promises it a high degree of autonomy, a legal system separate from that of mainland China and an independent judiciary.

The Department of Immigration said it respected the court's decision.

"We are studying the judgment carefully and shall seek legal advice as necessary before deciding the way forward," it said.

In a 45-page judgment, the judges said the director of immigration's assertion that an obvious difference existed between marriage and a civil partnership rested on "shaky foundations".

The court also said that while the director of immigration's policy aimed to attract foreign talent, the act of rejecting same-sex partners was counter-productive.

"As is evident from the attempted intervention of the banks and law firms, the ability to bring in dependants is an important issue for persons deciding whether to move to Hong Kong," it said.

Veteran LGBT activist Billy Leung, who arrived at court with a small rainbow flag, said he knew at least six same-sex couples who had chosen not to move to Hong Kong or had left the city in the past five years over what they described as a lack of LGBT-friendly policies.

"The struggle is real," he said.