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WATCH: BBC security correspondent Frank Gardner looks at the key evidence
The war in Ukraine has reached a critical point. Where it goes from here could decide the country’s future and affect the security of Europe.
In the 18 months since Russia invaded, the Ukrainians have mostly been on the defensive, preventing Moscow’s forces from seizing more territory.
But this summer, Ukraine – with the help of billions of pounds of Western military equipment – has gone on the attack, attempting to expel the Russians from land they previously captured in the east and south of the country.