The Ukrainian military and Russia-backed rebels each said they had given orders to pull back heavy weapons from the front line in eastern Ukraine in accordance with the recent cease-fire agreement.
But each also continued to accuse the other of violations of the truce as reports of shelling persisted.
Petro Kanonik, a spokesman at the Common Coordination Control Center for the Cease-Fire, said the two-week process of arms removal would begin on February 22.
In rebel-held Donetsk, senior separatist commander Eduard Basurin was quoted as saying the orders to complete the withdrawal over the next two weeks, starting from February 22, had been signed.
Meanwhile, in the government-controlled eastern city of Kharkiv, an explosion killed two people and injured at least eight others during a peace march on February 22.
The AFP news agency quoted Kharkiv police spokeswoman Natalya Zakharova as describing the blast as an apparent "terrorist" explosion, a term Ukrainian officials use for the Russia-backed separatists.
The blast occurred during a demonstration marking the first anniversary of the overthrow of former Ukrainian President Viktor Yanuovych.
Similar peace marches took in Kyiv and other parts of Ukraine on February 22, but not in the areas controlled by the separatists.
Kharkiv is located more than 200 kilometers from the front line.
Under the terms of the truce mediated by Germany and France and put into effect on February 15, the withdrawal of the weapons in eastern Ukraine was to have started on February 17 and to have been completed by March 3.
But it was delayed due to fighting in the strategic town of Debaltseve, which government troops pulled out of on February 18.
Pro-Russian troops quickly moved into the town to assert control, angering the cease-fire's pro-Kyiv backers.
The heavy-weapon-withdrawal announcements came after Ukraine and the separatists exchanged 191 prisoners late on February 21.
Each side continues to accuse the other of violating the cease-fire.
Kyiv said on February 22 rebels violated the cease-fire a dozen times during the night with artillery and rocket attacks. Military spokesman Andriy Lysenko said one Ukrainian serviceman had been killed and three wounded over the past day.
Explosions were heard around Donetsk early on February 22, and a rebel website says several buildings in the city were damaged by artillery.
With reporting by Reuters, AP, Interfax, AFP, dpa, and BBC