The revelation has been met with outrage from human rights groups who question whether the technology could end up being deployed against protesters.

As activists prepare to hold another mass demonstration against the government’s handling of a now-suspended extradition bill, the government’s official logs reveal that in the first quarter of this year the UK approved an export licence for £1.9m of “telecommunications interception equipment” to Hong Kong. This was just weeks before protests against the controversial proposed treaty with mainland China began in March. However, concerns about the Hong Kong authorities’ treatment of protesters date back to 2014 when they launched a crackdown on students campaigning against proposed changes to the electoral system.

Before the issuing of the current licence for interception equipment, the UK had approved three other licences for similar technology since the 2014 crackdown. The value of the three previous licences totalled £575,000.

“These licences need to be stopped now,” said Andrew Smith, of Campaign Against Arms Trade. “The Hong Kong authorities have a long and brutal record of cracking down on activists and punishing dissent. By selling them the means to spy on pro-democracy campaigners, the UK government has made itself complicit in these abuses.”

Last month the UN special rapporteur on freedom of opinion and expression, David Kaye, called for an immediate moratorium on the sale, transfer and use of surveillance technology. But the UK appears reluctant to sign up. “There was one licence issued to Hong Kong for telecommunications interception equipment in the latest quarter, for use in counter-terrorism, counter-narcotics, counter-trafficking operations and search and rescue operations,” said a spokeswoman for the Department for International Trade.

Campaigners questioned how the UK can determine what the exported devices will be used for. “Surveillance equipment is a weapon in the hands of many repressive governments, which can be used to monitor, to harass and to imprison people who are campaigning, exposing injustices, or simply telling fellow citizens what’s going on in their country,” said Nick Dearden of Global Justice Now. “If you sell intercept equipment to governments with a history of using that equipment to crack down on human rights, saying those governments gave you assurances they wouldn’t use it in a repressive way, is no defence. You are complicit in those human rights abuses.”