AN emergency meeting of European foreign ministers has been called amid an escalation of violence in Ukraine and warnings of a “grave deterioration” in relations between Russia and the EU.

Ukraine today said it now had evidence through an intercepted phone call that proved the Russian-backed militia in Ukraine’s south-eastern port of Mariupol was responsible for the rocket attack that killed 30 civilians and injured 100 others.

Britain’s Foreign Minister Philip Hammond today led the condemnation of the attacks, including one a day earlier in which 13 people were killed after a rocket struck a civilian bus in Ukraine’s embattled east, and called on Moscow to end its support of the rebel militia.

US president Barack Obama also put the blame squarely on Moscow and said his country would work with European partners to “ratchet up the pressure on Russia”.

EU foreign affairs chief Federica Mogherini appealed to Russia to exert its influence in the region to bring about peace and then used her Twitter account to call the urgent meeting of European foreign affairs leaders for this Thursday.

French President Francoise Hollande yesterday held talks with Ukrainian president Petro Poroshenko and was due to speak with Russian President Vladimir Putin tomorrow.

“I condemn in the strongest terms yesterday’s Russian-backed separatist attacks in the Black Sea port of Mariupol killing at least 30 innocent civilians, including children, and wounding many others. My thoughts are with the victims and their friends and families,” Mr Hammond said.

“I am deeply concerned about the significant escalation in violence in east Ukraine over the past week. Recent announcements by the separatist leaders of further offensives, and their blatant refusal to abide by the ceasefire, raise serious questions about the (peace) commitments they made at Minsk.”

He added: “Russia will be judged by its actions, not words. If the escalation in fighting continues, with tragic consequences for the local population, this will lead to a further grave deterioration in relations between the EU and Russia.”

President Obama said further sanctions against Russia was an option.

“We are deeply concerned about the latest break in the ceasefire and the aggression that these separatists — with Russian backing, Russian equipment, Russian financing, Russian training and Russian troops — are conducting, he said.

“I will look at all additional options that are available to us short of military confrontation and try to address this issue. And we will be in close consultation with our international partners, particularly European partners.”

Ukraine has accused Moscow of deploying 9000 troops to help rebels annex the eastern frontier of Ukraine; Moscow denied it had sent troops but said if any were there they were “volunteers”.

Russia’s foreign minister Sergei Lavrov spoke today with both US Secretary of State John Kerry and Ms Mogherini and told both the escalation in violence was of Ukraine’s making.

Ukraine’s military spokesman Colonel Andriy Lysenko said the situation was tense with continuous shelling Of Ukraine positions across the east of the country. He said between January 17 and 22, Ukraine troops killed 600 militants and Russian troops.