The UK is 'ready' to intensify sanctions against Russia if it does not stop destabilising eastern Ukraine, according to Prime Minister David Cameron.
It comes a day after pro-Russian rebels killed at least nine Ukrainians in fresh clashes.
European Union foreign ministers are also discussing new sanctions on Moscow.
A ceasefire has been broken regularly in eastern Ukraine since it was agreed in September.
And David Cameron says increased sanctions may be painful but necessary.
IN: "Of course...
OUT: ...more pressure."
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