The British Foreign Secretary, Philip Hammond, has accused Russia’s Vladimir Putin of acting like a “mid-20th century tyrant” and warned that he will “pay the price for what he is doing in Ukraine”.
As the leaders of Germany, France, Ukraine and Russia agreed to meet in Belarus to try and broker a peace deal, Mr Hammond appeared on Sky News to denounce the Kremlin's behaviour as "outrageous and outdated".
The US is considering moves to provide additional supplies and arms to the government in Ukraine - as Russia has been accused of doing with sectarian rebels - but the EU has denied the emergence of a transatlantic rift on the issue.
After meeting the Ukrainian president Petro Poroshenko and Russian foreign minister Sergei Lavrov, EU foreign policy chief Federica Mogherini said she respected the internal debate on the subject in the US and "it is up to them to discuss and decide".
"We are united when it comes to support to Ukraine ... we are united when it comes to economic pressure and we are united also on ... the need to have a political dialogue," she said.
Mr Hammond said a decision on whether Britain would also help arm the Ukrainian military was “under review”, but demanded Russia withdraw its troops not only from Donetsk but also from Crimea, which Putin annexed in March last year.
“Don't make it sound like that is an outrageous thing for us to demand [of Mr Putin],” the minister told Sky News’ Murnaghan programme.
“This man has sent troops across an international border and occupied another country's territory in the 21st century acting like some mid-20th century tyrant.
“We do not behave like that. Civilised nations do not behave like that in the 21st century. We live in a rules-based society. We want the Russian people to be part of that international community.
“We want Russia to enjoy the kind of economic growth and rising standards of living that people in the rest of Europe enjoy and we do not see any reason to tolerate this kind of outrageous and outdated behaviour from the Kremlin.”
After a joint phone call today involving Germany's chancellor Angela Merkel, the French president Francois Hollande, Mr Poroshenko and Mr Putin, the four agreed to talks in Minsk which will aim to agree an immediate ceasefire.
French Defence Minister Jean-Yves Le Drian, speaking on French television, said he feared a "dramatic spiral" in violence if dialogue with Moscow did not succeed.
Mr Hammond dismissed an earlier claim from France’s Mr Hollande that current talks were the “last chance for peace” in Ukraine – noting that a military conflict is already under way. But he agreed that a political solution was the only way to end the crisis, adding that “the Kremlin, Mr Putin, has to understand he will pay a political and economic price for what he is doing in the Ukraine”.
At least 5,000 people have been killed in eastern Ukraine since April 2014, when the country's Russian-backed president Viktor Yanukovich was forced out during mass street protests in Kiev.
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