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Russia has warned of "consequences" following confirmation that British-made drones were used in recent Ukrainian strikes in Russia.

The Russian embassy in the UK accused Britain of "deliberately opting for an escalation of the Ukraine crisis" as Kyiv has stepped up attacks on Moscow and other parts of the country in recent weeks.

In particular, the attacks have targeted oil refineries and warehouses of the largest online retailer Wildberries.

UK Prime Minister Andy Burnham has said London will continue "to support Ukraine 100%".

The BBC's Caroline Hawley explains what we know about Russia's warning.

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