In a rapidly escalating diplomatic feud over protests in Hong Kong, China told Britain to keep its "hands off" the city and "show respect."

British Foreign Secretary Jeremy Hunt vowed yesterday to maintain pressure on China over the treatment of protesters in Hong Kong, amid an escalating diplomatic row. He repeated that there would be "consequences" if Beijing breached commitments it made about rights in Hong Kong when Britain handed over control. Speaking to BBC radio, Hunt declined to specify, but said "you keep your options open." "What I wanted to do was to make the point clearly that this isn't something that we would just gulp and move on, this would be a very serious issue for the U.K.," he said.

After Hunt first warned of "serious consequences" on Tuesday, the Chinese Foreign Ministry hit back by accusing him of indulging in a colonial fantasy. The diplomatic offensive raged on in London, where Chinese Ambassador Liu Xiaoming hastily convened a press conference, demanding that Britain stop interfering and warning it risked "further damaging" bilateral ties. "I tell them: hands off Hong Kong and show respect," Liu said, according to the state-owned CGTN news site. "This colonial mindset is still haunting the minds of some officials or politicians." He spoke moments before being summoned by the Foreign Office for a private meeting with U.K. diplomatic service chief Simon McDonald.

The demonstrations sweeping the former British colony have also revived tensions inherent in the two sides' historic agreement on the global financial hub's handover to Chinese rule 22 years ago. Police have announced the arrest of 12 people who tried to disrupt a ceremony Monday marking the anniversary of Hong Kong's return from Britain to China in 1997. Another person was arrested for his alleged involvement in the storming of the legislature building that night. Eleven men and a woman were arrested over the Monday morning protest. They face various charges including possession of offensive weapons, unlawful assembly, assaulting a police officer, obstructing a police officer and failing to carry an identity document. The brief statement did not provide further details.

Britain insists that a 1984 agreement between London and Beijing ensuring Hong Kong would maintain its separate political, economic and social institutions until 2047 remains a binding document. Chinese officials in recent years have suggested they no longer consider themselves bound by the pact, although they have been reluctant to completely undermine those institutions that have made Hong Kong a magnet for global business with thousands of foreign companies and residents.