Updated

NATO said Wednesday that there is still no sign that any Russian troops have withdrawn from the Ukraine border, despite claims by Moscow that military units had begun moving to railway stations and airfields en route to their home bases.

In a statement carried by Russian news agencies, Russia's Defense Ministry claimed that military units in the Belgorod, Bryansk and Rostov regions were expected to arrive at their home bases before June 1.

Yet NATO, which estimates that Russia has 40,000 troops along the border with Ukraine, repeated Wednesday it could not yet see any signs of a pullout.

"What we know thus far is that there has been certain troop movements, but I have received no confirmation, either through Pentagon sources or NATO sources, that there has been a wholesale repositioning of those troops off the border," U.S. Army Secretary John McHugh told reporters in Tallinn, Estonia, according to Reuters.

The Kremlin claimed that Russian President Vladimir Putin ordered the withdrawal Monday in an apparent attempt to ease tensions with the West over Ukraine and avoid further sanctions.

Putin said Wednesday that "those who aren't seeing it should look better." He said the pullout will be clearly visible in satellite images, according to Russian news agencies.

The pullout was meant to create "favorable conditions for Ukraine's presidential vote and end speculations," Putin told reporters in Shanghai, China, where he attended a security summit.

Russian television on Wednesday broadcast footage of columns of tanks and howitzers towed by heavy trucks. It wasn't immediately clear where the footage was taken.

The ministry said its units will make most of the journey by air or rail to reduce the pressure on highways.

Gen. Vladimir Shamanov, the chief of the Russian Airborne Forces, said in televised remarks that battalions from three airborne divisions would return to their home bases within 10 days.

The Ukrainian government and the West have seen the Russian military buildup in the areas near the border as a possible precursor for grabbing more land following Russia's annexation of Crimea in March. The United States and the European Union slapped sanctions on members of Putin's entourage after Russia took Crimea, and have threatened more crippling sanctions if Moscow tries to invade eastern Ukraine or derail its presidential vote set for this Sunday.

But Putin said Wednesday that it would have made more sense for the Ukrainian authorities to have a constitutional referendum that would approve a new constitution before the election.

"It will be very difficult for us to develop relations with people, who come to power amid a punitive operation in southeastern Ukraine," he said.

Putin added that Russia has helped establish a dialogue between the central government in Kiev and people in the southeast.

"We have done everything to help start these contacts," he said.

Putin's pullout order has shown that he has no immediate intention to send the Russian army into Ukraine, where pro-Russian insurgents have seized government buildings and clashed with Ukrainian government forces in weeks of fighting that has left dozens dead.

The rebels have also faced a challenge from Ukraine's richest man, metals tycoon Rinat Akhmetov, who demanded an end to the mutiny which he said was destroying eastern Ukraine and called on workers to hold protests. The insurgents also faced angry local residents, increasingly exasperated over being caught in cross fire that have destroyed their housing and endangered their lives.

The Associated Press contributed to this report.