A panel of judges at Taiwan's top court began hearing a landmark case on Friday that could make the island the first in Asia to introduce same-sex marriage.

The case has been brought by a gay activist as well as municipal authorities from the capital, Taipei, the BBC reported.

Taiwan's parliament has also been debating whether to pass laws that would allow same-sex marriage.

A panel of 14 justices are hearing arguments and will debate whether a line in Taiwan's civil code, which states that marriage is between a man and a woman, is unconstitutional.

Veteran gay activist Chi Chia-wei, whose attempt at registering marriage with his partner in 2013 was rejected, had petitioned for the case to be heard.

Gay rights campaigners carrying rainbow flags, have turned up in front of the court in Taipei, as have anti-gay marriage protesters.

In December Taiwan's parliament had approved the first draft of a bill to legalise gay marriage, with a second reading due in months, the BBC reported.

President Tsai Ing-wen has previously said she would support marriage equality. Taiwan is known for its progressive values and energetic LGBTQ -- lesbian, gay, bisexual, transgender, and queer -- movement.