Ukrainian President Petro Poroshenko says he is ready to resume a cease-fire in his military campaign against pro-Russian separatists if certain conditions are met.
The Ukrainian president's website said Thursday that he discussed the situation in eastern Ukraine in a phone call with U.S. Vice President Joe Biden.
It quoted Poroshenko as telling Biden he is ready to return to a cease-fire as soon as it can be confirmed that both sides are observing it, and also on condition that all hostages are released and control over the Ukrainian-Russian border is established, with monitoring by the Organization for Security and Cooperation in Europe (OSCE).
Poroshenko declared a unilateral, week-long cease-fire June 20 and then extended it by three days. Citing lack of cooperation from rebels, he refused a second extension and ordered new military operations on Tuesday.
New defense minister
Earlier Thursday, the president replaced top defense officials, naming Valery Heletey as Ukraine's new defense minister, and Viktor Muzhenko as chief of the military's general staff.
Also Thursday, Russian President Vladimir Putin, German Chancellor Angela Merkel and French President Francois Hollande discussed the situation in Ukraine during a three-way telephone call.
Hollande’s office said he and Merkel called on Putin “to intervene with the separatists to get them to negotiate and reach an agreement with the Ukrainian authorities.”
The Kremlin said the Russian president “expressed deep concern in connection with the increase in casualties among the civilian population and a sharp increase in the number of refugees from southeastern Ukraine on Russian territory."
On Wednesday, the foreign ministers of Ukraine, Russia, France and Germany met in Berlin and said talks aimed at resuming a cease-fire between the Ukrainian military and pro-Russian rebels should begin no later than Saturday.
The diplomats announced their consensus in a statement as fighting raged near the Russian border. They said the preliminary talks will aim to establish an "unconditional and mutually agreed sustainable cease-fire" monitored by the Organization for Security and Cooperation in Europe.
Russian Foreign Minister Sergei Lavrov, speaking Wednesday after the Berlin meeting, condemned the Ukrainian leader's decision to end the unilateral cease-fire. He said that decision cost lives in eastern Ukraine and the "serious destruction of civilian infrastructure."
But he also promised that Moscow would use its influence with separatist leaders to bring about a bilateral truce.
Fighting in eastern Ukraine continued Thursday, with Ukraine’s border guard service reporting that rebel forces shelled the Dolzhansky border post with Russia, which Ukrainian forces took back from the separatists after Kyiv resumed its military operations earlier this week. Nine Ukrainian border guards were wounded in the shelling.
The separatists, for their part, were reported by Russian media as saying Thursday that Ukrainian artillery was shelling the rebel-held cities of Slovyansk, Kramatorsk and surrounding villages.
President Putin -- speaking hours after military operations resumed Tuesday -- repeated his commitment to protect Russian-speaking people in eastern Ukraine, "using the entire range of available means."
The United States and its European allies accuse Russia of arming the separatists in eastern Ukraine, and have demanded that the Kremlin stop the cross-border flow of fighters and military hardware into eastern Ukraine.