Ukraine's Interior Minister Arsen Avakov on Friday posted on his Facebook page that a large number of pro-Russian militants had left their base in Sloviansk, BBC reported.
Avakov also said that the military commander of the self-declared Donetsk Peoples' Republic (DPR), Igor Strelkov, was among those leaving, but this was not confirmed.
In response, a DPR spokesman denied that the militants had left Sloviansk.
Ukrainian President Petro Poroshenko Friday said that he was ready to return to a ceasefire provided it was observed by both sides, all hostages were freed and borders secured by government forces.
Ukrainian officials said Friday they had proposed indirect talks with rebel leaders but were still waiting for a response.