Liz Truss has branded China "the largest threat that we face to the free world" following criticism of her planned visit to Taiwan.
The former prime minister was blasted for "Instagram diplomacy" by her own Tory colleagues over the weekend amid concern her planned trip could upset the delicate political balance in the region.
But the ex-PM hit back on Monday and accused the UK along with other western countries of being "too dependent" on Beijing and not being tough enough.
Ms Truss had been widely expected to adopt a more hawkish stance towards China during her premiership, which was cut short following economic turmoil unleashed by her policies.
But her successor Mr Sunak adopted less hard-line language, with a review on foreign and defence policy in March describing China as an "epoch-defining and systemic challenge".
Speaking at the Copenhagen Democracy Summit Ms Truss said the West should not capitulate to "rhetorical bullying from authoritarian regimes".
"There's no doubt that the entire western world including the United States, including Europe, including the UK, has become too dependent on China, and that's a problem because it's given China leverage over us, and it's also a problem economically," she said.
"Yes, the UK needs to take more action but it's not just the UK, it's the continent of Europe, it's the United States."
Ms Truss also drew parallels between Russian President Vladimir Putin and Chinese leader Xi Jinping, arguing Chinese policy was "linked" to the war in Ukraine.
"I stand by my assertion that we should designate China as a threat. I think they're a very clear threat. I think they're the largest threat that we face to the free world," she said.
The visit comes during a sensitive time for relations between the West and and an increasingly assertive Beijing.
China views Taiwan as a breakaway province that will eventually be under its control and has not ruled out the use of force to achieve "reunification".
But Taiwan has its own government and considers itself independent from the People's Republic of China.
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Show all 50Relations deteriorated sharply following US house speaker Nancy Pelosi's visit to the island in August last year, and there are fears Ms Truss's trip could escalate things further.
Alicia Kearns, Tory chair of parliament's foreign affairs select committee, said last week that Ms Truss only wanted to visit the country to boost her profile.
“The trip is performative, not substantive. It is the worst kind of example of Instagram diplomacy," she said.
“It is deeply unhelpful because it escalates the normal situation in Taiwan."
The government has not commented on the matter, other than to say it would not get involved with “independent travel decisions of a private citizen who is not a member of the government”.
