MOSCOW (Reuters) - Russian President Vladimir Putin said on Saturday he supported Ukraine President Petro Poroshenko's call for a ceasefire, but added that without"practical actions" to start negotiations the plan would not be viable.

"Vladimir Putin supports the decision of the President of Ukraine Petro Poroshenko to cease fire in the south-east of Ukraine, as well his stated intentions to take a number of concrete steps to achieve a peaceful settlement," the Kremlin said in a statement. "However, the Russian head of state drew attention to the fact that the proposed plan without practical actions aimed at the beginning of the negotiation process will not be viable and realistic."

But Mr Putin will not accept a peace proposal from his Ukrainian counterpart Petro Porochenko with the "characteristics of an ultimatum" for separatists in eastern Ukraine, he said on Saturday.

"Mr Porochenko's peace plan should not have the characteristics of an ultimatum for the insurgents," he said in a statement.