Prime Minister Liz Truss is expected to tell the United Nations that Britain will no longer be "strategically dependent on those who seek to weaponise the global economy" as she calls for the free world to "push back against authoritarian aggression".
Ms Truss will address the UN General Assembly later on Wednesday as it gathers under the shadow of a large-scale war in Europe.
She will tell the representatives how she plans to make sure the British economy is free from malign interference, including increasing energy independence and safeguarding the security of supply chains.
In her speech, the prime minister is expected to say: "We are reforming our economy to get Britain moving forward once again.
"The free world needs this economic strength and resilience to push back against authoritarian aggression and win this new era of strategic competition.
"We will no longer be strategically dependent on those who seek to weaponise the global economy."
Ms Truss will also tell the General Assembly that the G7 and other like-minded partners must act as an "economic NATO", collectively defending our prosperity and coming to the aid of any partner targeted by an aggressive regime.
She will reiterate a commitment to protecting the UK and its allies, including increasing defence spending to 3% of GDP by 2030.
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The prime minister is expected to say: "Just as we are building a plan for growth at home, we are also developing a new blueprint for our engagement with the world.
"We will build resilience and collective security - because they are vital for freedom and democracy. We will be a reliable, trustworthy and dynamic partner."
She will add: "This is a decisive moment in British history, in the history of this organisation, and in the history of freedom.
"The story of 2022 could have been that of an authoritarian state rolling its tanks over the border of a peaceful neighbour and subjugating its people.
"Instead, it is the story of freedom fighting back… But this must not be a one off….
"…Britain's commitment to this is total.
"Together with our friends and allies around the world, we will continue to champion freedom, sovereign and democracy.
"And we will define this new era as one of hope and progress."
On Tuesday, Ms Truss told Sky News she was prepared to be unpopular over her plan to cut taxes while also promising billions of pounds to help consumers pay rising energy bills.
She insisted that the tax cut plan would ultimately benefit the British economy.