Ukrainian rebels claim they are beginning heavy weapons pullback

Russia-backed rebels ride on an armored vehicle in the center of Debaltseve, Ukraine, Monday, Feb. 23, 2015. After weeks of relentless fighting, the embattled Ukrainian rail hub of Debaltseve fell last week to Russia-backed separatists. (AP Photo/Vadim Ghirda) (The Associated Press)

A toy tank lies with debris from a heavily damaged apartment building in Debaltseve, Ukraine, Monday, Feb. 23, 2015. After weeks of relentless fighting, the embattled Ukrainian rail hub of Debaltseve fell last week to Russia-backed separatists. (AP Photo/Vadim Ghirda) (The Associated Press)

A woman holds a picture of Ukrainian pilot Nadezhda Savchenko during a rally outside the Russian Embassy in Kiev, Ukraine, Tuesday, Feb. 24, 2015. Ukrainian pilot Nadezhda Savchenko was captured by Russia-backed rebels during fighting in eastern Ukraine. The Kiev government has so far been unsuccessful in seeking the extradition of Savchenko who was elected a member of the Ukrainian parliament in the October 2014 Ukrainian parliamentary election. (AP Photo/Sergei Chuzavkov) (The Associated Press)

Russian-backed rebels in eastern Ukraine say they have begun a large-scale pullback of heavy weapons in line with an international peace plan that aims to form a wide buffer zone between separatists' and Ukrainian forces' artillery.

The claim Tuesday by Eduard Basurin, a top rebel commander, could not immediately be confirmed. Michael Bociurkiw, a spokesman for the observer mission that is monitoring the fighting in eastern Ukraine, said he could not comment until receiving monitors' reports at the end of the day.

The peace plan that was signed Feb. 15 calls for heavy weapons to be pulled back by each side from the front line by 25 to 70 kilometers, depending on their caliber.

A rebel website cited Basurin as saying about 100 122-mm howitzers would be moved on Tuesday.