Military units in the Belgorod, Bryansk and Rostov regions started marching back and are expected to arrive at their home bases before June 1, the defense ministry said in a statement carried by Russian news agencies.

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 Russian pullout.

President Vladimir Putin ordered the withdrawal Monday in what could be an attempt to ease tensions with the West over Ukraine and avoid further sanctions.

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.

Putin’s pullout order and his statement welcoming the election, which he had previously urged to postpone, 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.