China has blasted a senior Tory MPs’ “colonial” approach to pro-democracy protests in Hong Kong and warned Britain against “interfering” in its affairs.

Beijing’s ambassador to London said the likes of Tom Tugendhat, chair of the Commons foreign affairs committee, were acting like Hong Kong was still part of the British empire.

And days after Foreign Secretary Dominic Raab was warned by China to stop interfering, Liu Xiaoming told “foreign forces” to “respect China’s sovereignty and security”.

Tugendhat on Tuesday said Britain should give citizenship to Hong Kong Chinese people to reassure them amid increasingly violent protests and police crackdowns. 

Demonstrators, some waving union jack flags, say they are fighting the erosion of the “one country, two systems” arrangement enshrining some autonomy for Hong Kong when China took it back from Britain in 1997.

But China has begun to characterise the protests as something approaching “terrorism” while amassing paramilitary police just over the border from the city on the mainland, prompting fears of escalation. 

Downing Street has expressed its concern about the violence and called for “calm from all sides”.

But Lord Patten, the UK’s final colonial governor of the territory, has been vocal in calling for Boris Johnson to act in defence of Hong Kong’s freedoms.

Liu warned the UK against “saying or doing anything that interferes” in the nation’s affairs or rule of law.

“I sincerely hope that people from all walks of life in the UK will have a clear understanding of a big picture, act in the interests of Hong Kong’s prosperity and stability and refrain from saying or doing anything that interferes in Hong Kong’s affairs or undermines the rule of law in Hong Kong,” he said.

Asked about Tugendhat’s plan to give Hong Kong Chinese people British citizenship, he said: “I think some politicians in this country still know their body is still lived in the 21st century but their hands are still in the colonial days.

“I think some of them still regard Hong Kong as part of the British empire and they treat Hong Kong as part of the UK.

“They are going to have to change their mindset, put them in the proper position and regard Hong Kong as a part of China, not as a part of the UK.

The ambassador accused some protesters of showing “signs of terrorism” after they occupied Hong Kong airport and warned them they cannot drag the territory into a “dangerous abyss”.

He said there must be justice “no matter who they are and however they hard they try and whitewash their actions”.

“If anyone in this country questions this point, let me ask them this: Would the UK allow extremists to storm the Palace of Westminster and damage its facilities and get away with it?,” he continued.

“Would the UK give permission for attacking police officers with lethal weapons or set fire to police stations without any punishment?

“Would the UK allow so called pro-democracy rioters to occupy the airport, obstruct traffic, disturb social order or threaten the safety and people’s life and property?

“Aren’t all these regarded as crimes in the UK?”

Responding, Tugendhat said: “China’s treatment of its own citizens is a matter for them.

“British citizens, whether in the UK or overseas, should enjoy the option to live under the rule of law.
“Changing the status of British nationals overseas is a sovereign decision for the UK parliament.

“No one else.”

The Chinese foreign ministry previously slapped down Raab after he spoke with Hong Kong chief executive Carrie Lam and stressed the need for “meaningful political dialogue” and an independent investigation.

Spokeswoman Hua Chunying said it was “simply wrong for the British government to directly call Hong Kong’s chief executive to exert pressure”.

Protests have taken place in Hong Kong – a former British colony returned to China in 1997 – over the summer.

They were initially triggered by controversial extradition proposals that would have allowed some suspects to be sent to mainland China for trials.

Despite the government suspending the planned legislation, protesters have pressed on with broader calls for it to be scrapped entirely and demands for democratic reforms.

The Sino-British Joint Declaration signed in 1984 paved the way for the handover and said Hong Kong would enjoy a “high degree of autonomy, except in foreign and defence affairs” and be “vested with executive, legislative and independent judicial power”.