Speaking to Channel 4 News, Mr Hunt said China needs to honour a 1984 treaty that guarantees basic freedoms to the former British colony for 50 years.
The foreign secretary, Jeremy Hunt, has warned China of “serious consequences” if it fails to honour its agreement over Hong Kong.
Speaking to Channel 4 News, Mr Hunt said China needs to honour a 1984 treaty that guarantees basic freedoms to the former British colony for 50 years.
His comments come amid huge protests in Hong Kong, with millions of people demonstrating against a bill that would allow people in the territory to be extradited to mainland China.
Earlier this week, China said that the UK should stop “gesticulating” about the issue because it no longer has any responsibility for former colony.
But Mr Hunt said he was “very concerned”, explaining: “We want to be the best of friends with China; we want to trade with China. But we expect all countries that we have internationally binding agreements with to honour those agreements.”
“The United Kingdom wants to ensure that what was agreed to, back in 1984, is honoured for those fifty years.”
He added: “If that agreement, between the United Kingdom and China, was not honoured then there would be serious consequences. Of course there would be.”
However, he refused to say what those consequences would be, saying “it’s not smart diplomacy” to spell them out in advance.
But the foreign secretary added: “I made it clear that Britain – one of the oldest democracies in the world – is standing foursquare behind the agreement we reached with China over the future of Hong Kong.”
The warning comes as Mr Hunt challenges Boris Johnson to become the next Conservative Party leader and UK prime minister.
Mr Johnson did not agree to be interviewed by Channel 4 News ahead before voting started by party members – but has said that he would attend an interview with Channel 4 News at some stage.
Jeremy Hunt said he would be “more than happy” to serve in a government led by Mr Johnson. Likewise, he “very much hopes” that Mr Johnson would be part of his team, should he become prime minister instead.
Discussing Brexit, Mr Hunt defended his pro-Brexit position, despite previously campaigning to remain in the EU.
He told Channel 4 News the UK can “make a tremendous success of Brexit,” before going on to describe the current situation as “the biggest constitutional crisis that we’ve had in my lifetime”.
“I am like millions of people who voted remain who just want to get on and deliver Brexit – because we’re democrats,” Mr Hunt said.
“When I go around the world as foreign secretary, people have actually a whole lot more respect for us than we sometimes have for ourselves.”
“They don’t say you can’t make a success of Brexit,” he said, “they just want us to get on with it.”
Mr Hunt added: “I think, after this election, what the people of this country want is the Conservative Party and the Conservative government to come together to find a solution to the biggest constitutional crisis that we’ve had in my lifetime.”
He also admitted that the only way to win back the support of voters who have switched to Nigel Farage’s Brexit Party is to finally deliver Brexit, saying there was “no other way”.