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By Steve Holland
ABOARD AIR FORCE ONE, May 7 (Reuters) - The White House said on Wednesday that it has seen no evidence that Russian President Vladimir Putin has pulled Russian troops back from the Ukrainian border, and said it wants a referendum on secession to be canceled, not merely postponed.
"We would certainly welcome a meaningful and transparent withdrawal" of Russian military forces from the border region, White House spokesman Josh Earnest told reporters traveling with President Barack Obama to Arkansas and California.
"To date, there has been no evidence that such a withdrawal has taken place," Earnest said.
Earnest was responding to a question about an announcement by Putin that he had called on pro-Moscow separatists in Ukraine to postpone a vote on secession just five days before it was to be held, and would pull back troops from the border.
"We've said repeatedly that the referendum is illegitimate, illegal. Secretary of State Kerry referred to this referendum as bogus. So we don't believe this referendum should be postponed, we believe it should be canceled," Earnest said.
The referendum had been planned by pro-Russian insurgents seeking autonomy and independence for portions of eastern Ukraine. (Reporting By Steve Holland, writing by Mark Felsenthal and Roberta Rampton; Editing by Chizu Nomiyama and Susan Heavey)