Western allies must "double down" on support for Ukraine amid the ongoing war with Russia, Foreign Secretary Liz Truss has said. 

In a keynote foreign policy speech, Ms Truss said Russian forces must be driven "out of the whole of Ukraine" as she urged the West to supply heavy weaponry to Kyiv. 

Speaking at Mansion House in London, she said the UK needed to strengthen its military while building alliances with free nations around the world, using their economic power to deter aggressors who “do not play by the rules”.

She said: "The war in Ukraine is our war. It is everyone's war because Ukraine's victory is a strategic imperative for all of us.

"Heavy weapons, tanks, aeroplanes - digging deep into our inventories, ramping up production. We need to do all of this."

She called for the G7 group of leading industrialised nations to act as an “economic Nato” defending collective prosperity and criticised China which has refused to condemn the invasion of Ukraine, while increasing imports from Russia.

“China is not impervious. They will not continue to rise if they do not play by the rules,” she said.

“China needs trade with the G7. We represent around half of the global economy. And we have choices.

“We have shown with Russia the kind of choices that we’re prepared to make when international rules are violated.”

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Ms Truss said the international architecture intended to guarantee peace and prosperity had failed Ukraine in the face of an attack by a “desperate rogue operator”, in the shape of Vladimir Putin, with no interest in international norms.

“Russia is able to block any effective action in the UN Security Council. Putin sees his veto as a green light to barbarism,” she said.

In the short term, she said Western allies must “double down” on support for the government in Kyiv, providing the heavy weaponry it needs “to push Russia out of the whole of Ukraine”.

At the same time, she said the events of the past months must be “a catalyst for wider change”.

“Now we need a new approach, one that melds hard security and economic security, one that builds stronger global alliances and where free nations are more assertive and self-confident, one that recognises geopolitics is back,” she said.

At home, she said that should mean an increase in defence spending with the Nato minimum of 2% of national income a “floor not a ceiling”.

At the same time, the UK needed to build a series of strong partnerships with like-minded countries around the world in a “network of liberty”.

In Europe, Finland and Sweden should, if they choose to join Nato, be integrated into the alliance “as soon as possible”, while states like Moldova and Georgia – which are not Nato members – should have the means to maintain their sovereignty and freedom.

Nato, which has traditionally been focused on the defence of Europe, needed to adopt a “global outlook”, working with allies like Japan and Australia to ensure the Pacific is protected and democracies like Taiwan are able to defend themselves.

Ms Truss said they had to be prepared to stand up to “aggressors” who try to exploit their economic power as a “tool of foreign policy” to exert control and to coerce others.

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“Access to the global economy must depend on playing by the rules. There can be no more free passes,” she said.

“We are showing this with the Russia-Ukraine conflict – Russia’s pass has been rescinded.

“The G7 should act as an economic Nato, collectively defending our prosperity. If the economy of a partner is being targeted by an aggressive regime we should act to support them. All for one and one for all.”