Ukrainian President Petro Poroshenko has warned a ceasefire now in place may not be extended beyond Friday night when it is due to expire if peace talks with pro-Russian separatists fail to yield a favorable outcome.
"Most important is the securing of a long-term ceasefire as a necessary condition for substantive talks between the authorities in Kiev and representatives of the southeastern regions," Putin said. "We sincerely strive to help the peace process," he told delegates at a diplomatic ceremony in the Kremlin.
Western governments have piled pressure on Putin to take steps to disarm the rebels who Kiev accuses of numerous breaches of the truce aimed at giving the two sides time to find a political solution to the crisis.
Putin also said that the violence in Ukraine had forced tens of thousands of Ukrainians to seek refuge abroad, including in Russia, Reuters reported.
Other Russian officials speaking elsewhere on Friday threatened Ukraine with "grave consequences" and economic measures after Kiev signed an agreement with the European Union.