Prime Minister David Cameron said Tuesday he was "deeply concerned" about escalating protests in Hong Kong and reminded China of its obligations towards the former colony.
Britain handed control of Hong Kong to China in 1997 under an agreement that enshrined the "one country, two systems" principle, which was meant to preserve Hong Kong's capitalist system and way of life for a period up to 2047.
Asked if he felt any obligation to speak up for the city, where tens of thousands of people have taken to the streets to demand genuine democracy from China, Cameron said: "Of course, I feel a deep obligation."
He told Sky News television: "When we reached the agreement with China there were details of that agreement about the importance of giving the Hong Kong people a democratic future within this two-systems approach that we were setting out with the Chinese.
"So, of course, I am deeply concerned about what is happening and I hope this issue can be resolved."
The demonstrators have demanded full universal suffrage after Beijing last month said it would allow elections for the semi-autonomous city's next leader in 2017 but would vet the candidates — a decision branded a "fake democracy".
Beijing on Tuesday called the street protests "illegal".
China on Tuesday described major pro-democracy demonstrations in Hong Kong as illegal, adding that it supports the Hong Kong government's handling of the protests.
"We fully believe in and support the Hong Kong SAR government to deal with this issue," foreign ministry spokeswoman Hua Chunying said at a regular briefing.
Hua said that beginning Sunday "an illegal assembly" was held in Hong Kong followed by "a series of illegal activities damaging the rule of law".
"We oppose all illegal acts in Hong Kong," she added.
Hua chided countries including the United States and Britain for making statements on the demonstrations.
"Hong Kong affairs fall within China’s domestic affairs," she said. "We urge caution to outside parties and call for them not to interfere with China's internal affairs in any way."
On Monday, the Foreign Office said people in Hong Kong should be able to exercise their right to demonstrate within the law, adding: "These freedoms are best guaranteed by the transition to universal suffrage."
