The EU agreed Thursday to expand its sanctions against Russia as Ukraine's warring parties announced fresh truce talks to end a surge in fighting between Kiev and Kremlin-backed rebels.
Former Soviet leader Mikhail Gorbachev warned meanwhile that the threat of further sanctions risked turning the new Cold War atmosphere into a globally destabilising "hot" armed conflict between Moscow and the West.
During emergency talks called after dozens died in fighting in the east Ukrainian port of Mariupol, EU foreign ministers overcame reluctance from Greece's radical new government to reach a deal to tighten sanctions.
"I cannot say I am happy that we have taken this decision because the situation on the ground is nothing to be happy about," EU foreign policy chief Federica Mogherini told a press conference in Brussels.
"But the one thing I can be happy about is that we have kept our unity."
Kiev and local officials said six civilians and five Ukrainian soldiers were killed over the previous 24 hours, adding to the UN's confirmed death toll of 5,100 for the conflict in the former Soviet state.
The EU ministers agreed to extend, by six months until September, a series of targeted sanctions hitting more than 100 Russian and Ukrainian figures, which were introduced after the annexation of Crimea in March 2014, according to a statement after the talks.
They also agreed to come up with more names to be hit with the travel bans and asset freezes within a week.
The EU ministers further agreed to start work on further "appropriate action" if Moscow and the rebels keep breaching a largely disregarded peace deal signed in Minsk, Belarus, in September.
That could open the door for the widening of much tougher sectoral sanctions hurting the Russian economy which were introduced after the shooting down of Malaysia Airlines flight MH17 over eastern Ukraine in July.
Greece's new Prime Minister Alexis Tsipras, who is close to Russia, had raised doubts about the need for more sanctions earlier in the week, but fears that Athens could veto new measures failed to materialise.
- Gorbachev 'hot war' warning -
The West says Russian forces are in Ukraine supporting the rebels -- a charge the Kremlin denies -- and has urged Moscow repeatedly to respect the Minsk deal.
In a new development, the contact group of representatives of Ukraine, Russia and the OSCE will hold further peace talks in Minsk on Friday, the Belarus foreign ministry said.
Ukraine's western-backed President Petro Poroshenko had earlier called for urgent talks, saying they should lead to "an immediate ceasefire and the withdrawal of heavy weapons from the line of contact."
Pro-Russian militants last week pulled out of peace talks and announced a new offensive that was followed by a rocket attack on the strategic port of Mariupol in which 31 civilians died.
Gorbachev, the last Soviet leader, appeared to pin the blame on the West for the worsening situation, saying sanctions which had cut Russian access to US and European capital markets threatened to spiral into open warfare.
"Where will that lead all of us? A Cold War is already being waged openly. What's next?" the 83-year-old Nobel peace prize winner asked. "Unfortunately I cannot say for sure that a Cold War will not lead to a 'hot' one."
Russia's resurgence has alarmed eastern members of the EU that used to be in the Soviet sphere of influence.
Poland, which has taken a harsh tone against Moscow, said Thursday it will soon allow civilians to sign up for military training as it boosts its defence system due to anxiety over events in Ukraine.
The Ukrainian rebels have made good their threat to push into the important eastern industrial lands that still answer to Kiev, with fears that they could open up a land corridor linking Russia to the annexed Black Sea peninsula of Crimea.
Poroshenko's office said US Vice President Joe Biden on Wednesday "expressed his firm support for the Ukrainian president's actions and spelled out the possibility of expanding US sanctions against Russia in case of a further escalation."
Western sanctions combined with a slump in oil prices have plunged Russia into recession and seen Standard and Poor's slap a "junk" rating on Moscow's debt.