Hong Kong Chief Executive Carey Lam said today that the Chinese government will not back down from its plans for new city national security legislation even after Britain criticizes the move.

The law on national security - which the Chinese People's National Assembly approved the principle of imposing but not yet completed - provides penalties for separatist, "terrorist", sabotage and foreign activities in the semi-autonomous city.

Beijing decided to impose this law after a wave of pro-democracy demonstrations, which sparked international opposition and led to the return of unrest again.

Lam expressed her position on the new Chinese legislation during a visit to Beijing today, accompanied by Justice Minister Teresa Cheng, Security Minister John Lee and Police Commander Chris Tang.

British Prime Minister Boris Johnson had assured - earlier today - that his country would not abandon the Hong Kong people if China imposed a national security law contrary to its international obligations under an agreement concluded in 1984.

"Hong Kong is successful because its people are free ... if China goes ahead, this will be a direct conflict with its obligations under the joint declaration, that legally binding treaty registered with the United Nations," Johnson wrote in The Times.

"If China goes ahead with reinforcing their concerns, Britain's conscience will dictate that it not shake its shoulders and let go, but we will fulfill our obligations and provide an alternative," he added.

Johnson also reiterated Britain’s promise to make Hong Kong residents of the British national passport hold a way to obtain British citizenship, enabling them to permanent residency in the United Kingdom.