Boris Johnson has said he does not want to become a "knee-jerk Sinophobe" as Britain suspended its extradition treaty with Hong Kong and imposed an arms embargo on the former colony.
The British prime minister said he had "serious concerns" about China's behaviour but stressed the need for a "balanced" approach as he resisted pressure from MPs to take a tougher line with Beijing.
Mr Johnson is treading a diplomatic high-wire over relations with the world's second most powerful country, which has accused Britain and the US of wanting to start a "new Cold War".
While he said the measures announced yesterday were "tough", he stopped short of imposing sanctions on China or on named individuals as Tory hardliners have advised.
Foreign Secretary Dominic Raab announced yesterday that Britain's extradition treaty with Hong Kong would be suspended immediately after China imposed a new security law on the region.
He also included Hong Kong in an arms embargo in place since 1989 against mainland China, and extended it to equipment that could be used for repression, including shackles and smoke grenades.
Beijing had warned of reprisals if Britain took further action over Hong Kong, but Mr Raab insisted the UK "will not buck and bow" in the face of such threats.
Five years after David Cameron, then prime minister, declared a "golden era" of China-UK relations, the two countries are at odds over not only Hong Kong but also telecommunications giant Huawei, human rights abuses and Beijing's handling of the coronavirus outbreak.
Mr Johnson said: "I'm not going to be pushed into a position of becoming a knee-jerk Sinophobe on every issue, somebody who is automatically anti-China. But we do have serious concerns."
He said he would not "completely abandon our policy of engagement" with China, adding: "You have got to have a calibrated response and we are going to be tough on some things but we are also going to continue to engage."
Mr Raab has accused the communist regime of committing "gross, egregious human rights abuses" against the country's mostly Muslim Uighur population in north-western Xinjiang province. He was pressed by some Tory MPs to consider sanctions against named individuals, over the alleged treatment of the Uighurs and over Hong Kong, with some calling for Carrie Lam, Hong Kong's chief executive, to be among them.
Mr Raab did not rule out sanctions eventually.