Hong Kong’s largest teachers’ union has joined the exodus from the alliance that organises the city’s annual Tiananmen Square vigil, citing the “worsening political situation”.

The opposition-leaning Professional Teachers’ Union (PTU) confirmed to the Post on Thursday that it decided to quit the Hong Kong Alliance in Support of Patriotic Democratic Movements of China last month following a meeting of its 39-member executive committee.

“We made the decision grudgingly, but given the worsening situation we had to do so,” PTU president Fung Wai-wah said. “Following a discussion, the executive committee agreed to take the step collectively although we did not conduct a vote.”

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He added: “But our stance on vindicating the 1989 June 4 crackdown remains unchanged ... We do not rule out working together with the alliance sometime in the future, depending on the situation by that time.”

Alliance spokesman Simon Leung Kam-wai said he believed the union’s withdrawal would not have a significant impact on the group’s operation, but he respected its decision to quit.

The alliance has five “operational goals”, comprising the release of dissidents, vindication of the 1989 pro-democracy movement, accountability for the Tiananmen Square crackdown, an end to “one-party rule” in mainland China, and to build a democratic country.

Pro-establishment figures previously argued it could amount to an act of subversion under the Beijing-imposed national security law – which came into effect in June last year – for the alliance or others to call for an end to one-party rule.

The 32-year-old alliance has been under increasing pressure in recent months. On Tuesday, it was fined HK$8,000 after it admitted operating its June 4 museum without a proper licence.

Police earlier banned its annual June 4 vigil in Victoria Park for the second year in a row, citing coronavirus restrictions.

The alliance, which used to have more than 200 member groups, started to see a wave of withdrawals from April including by the Hong Kong Association for Democracy and People’s Livelihood and district councillor Leung Yiu-chung’s office.

Simon Leung said the alliance had not kept count of the number of groups that had quit as it only looked at the figures at the end of each year.

The organisation, which has insisted it will keep operating, announced last month that seven of its 14 committee members had quit, while all of its full- and part-time staff, fewer than 10 employees, would be laid off by the end of this month.

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