Singapore’s gay rights activists are holding an annual rally which foreigners are banned from attending under new laws.
Only Singapore citizens and permanent residents are allowed at the event, which has come under increasing restrictions.
There are fears that the Pink Dot rally will be diminished, although organisers still expect a significant crowd.
Gay sex is illegal in socially conservative Singapore.
Previous Pink Dot rallies have been open to everyone. But because it is illegal for foreigners to take part in political protests in Singapore, they were technically always only there as observers.
Recent changes to Singapore’s laws classify anyone attending the event as a participant so organisers announced in May that they had no choice but to bar foreigners altogether.
Foreign companies such as Google and Goldman Sachs, which had previously given funding, have also been banned from sponsoring the event this year. This prompted about 100 local firms to step in to provide sponsorship.
Pink Dot, which has been held annually in a small park since 2009, has grown significantly over the years and has sparked a backlash among conservatives.
In 2014, religious groups held a counter-campaign called Wear White.
The gay rights movement has gained significant momentum in some parts of Asia.
In May, a Taiwanese court ruled in favour of gay marriage, paving the way for Taiwan to become the first place in Asia to legalise same-sex unions.