Confirm and verify

By Matt Robinson and Darya Korsunskaya

DONETSK, Ukraine/MOSCOW (Reuters) - Russian President Vladimir Putin called on pro-Moscow separatists in Ukraine to postpone a vote on secession just five days before it was to be held, potentially pulling Ukraine back from the brink of violent dismemberment.

It was the first sign the Kremlin leader has given that he would not endorse a referendum planned for Sunday by pro-Russian rebels seeking independence for two provinces in the east, and Russian analysts said they believed the rebels would heed Putin's call to put off the vote.

In what could be a breakthrough in the worst crisis between East and West since the Cold War, Putin also announced he was pulling Russian troops back from the Ukrainian border.

NATO, the Pentagon and the White House all said they had seen no signs of a Russian pull-back from the frontier, where Moscow has massed tens of thousands of troops, proclaiming the right to invade Ukraine to protect Russian speakers.