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KIEV, May 7 (Reuters) - Ukraine dismissed as "hot air" Russian President Vladimir Putin's appeal to pro-Russian separatists in eastern regions on Wednesday to postpone a referendum on independence, the Interfax-Ukraine agency said.
Prime Minister Arseny Yatseniuk urged Russia to stop what he called its support for "terrorists" and press them to lay down their arms and surrender to Ukrainian authorities.
Putin had called on separatists to defer the referendum, called for Sunday in an area where a string of cities have fallen under the control of militants Kiev and the West charge are inspired by Moscow and helped by Russian special forces. Kiev has ruled the referendum illegal.
"Vladimir Vladimirovich (Putin), trading in hot air is not becoming of you as the president of a big country," the agency quoted Yatseniuk as saying at a government meeting in the region of Kharkov.
He said Ukraine had never called the referendum and if "terrorists and separatists" supporting Russia had received a command to "postpone something that was never planned", then that was something they must resolve among themselves.
Putin made his proposal after talks in Moscow with the head of the Organisation for Security and Co-operation in Europe, who said the security and rights body would soon propose a "road map" to end the Ukraine crisis.
Yatseniuk expressed surprise that Ukraine's affairs had been discussed in Moscow without Ukrainian participation, but he said he hoped the OSCE road map would reflect Ukrainian ideas, according to Interfax-Ukraine. (Editing by Andrew Roche)