Hong Kong police have banned next month's vigil marking Beijing's deadly Tiananmen Square crackdown, organisers said Thursday, the second year in a row that authorities have refused permission.

The Hong Kong Alliance, which has organised the annual vigil for more than three decades, sent a short statement to reporters confirming police had refused permission and that a longer response would be issued shortly.

Hong Kong has regularly marked the anniversary of Beijing's deadly 1989 repression of protests in Tiananmen Square with huge candlelight vigils.

But last year's event was banned for the first time, with police citing the coronavirus pandemic and security fears following huge democracy protests that rocked Hong Kong the year before.

Tens of thousands defied the ban and massed peacefully at the vigil's traditional site in Victoria Park.

Since then prosecutors have brought charges against more than two dozen prominent democracy activists who showed up at the vigil, some of whom have already been jailed.

Hong Kong's refusal comes two days after police in neighbouring Macau also banned any Tiananmen vigils saying the event would "incite subversion".

It is the first time authorities have made clear a political reason for banning remembrance of the 1989 Tiananmen crackdown, an event that has largely been purged from collective memory on the mainland.