BY PETER LEONARD
MARIUPOL, Ukraine (AP) -- Shelling resounded on the outskirts of a Ukrainian port city Friday as Russian-backed rebels pressed their offensive in the strategically key southeast just hours ahead of talks that are widely hoped to bring a cease-fire.
Associated Press reporters heard heavy shelling on Friday morning north and east of Mariupol. The strategic city of about 500,000 lies along the Sea of Azov, between Russia to the east and the Russia-annexed Crimean Peninsula to the west.
The sound of incoming and outgoing shelling from different directions appeared to indicate that rebels have partially surrounded the area and are probing its defenses. The onslaught could be intended to raise the pressure on the Ukrainian government ahead of peace talks in Minsk, Belarus, which are expected to lead to a cease-fire.
Seizure of Mariupol would give the rebels a strong foothold and raise the threat of the rebels carving a land corridor between Russia and Crimea, the Black Sea peninsula that Russia annexed in March. If that happens, Ukraine would lose another chunk of sea coast and access to rich hydrocarbon resources the Sea of Azov is believed to hold.
The rebel offensive follows two weeks of rebel gains that turned the tide of the war against Ukrainian forces, who until recently had appeared close to crushing the five-month rebellion in the east.
Ukraine and the West say the rebel counterattack was spearheaded by regular Russian army units, a charge the Kremlin has denied.
Representatives of Ukraine, Russia, the rebels and the Organization for Security and Cooperation in Europe are to meet later Friday in Minsk for talks on ending the conflict. Both Ukraine's president and rebel leaders say they are prepared for a cease-fire if the talks succeed.
On Thursday, President Petro Poroshenko said while attending a NATO summit in Wales that he was ready to order a cease-fire in eastern Ukraine if a deal is signed. The rebels said they were ready to declare a truce if agreement can be reached on a political settlement for the mostly Russian-speaking region.
As head of state, Poroshenko said he is "ready to do my best to stop the war," and he voiced "careful optimism" about the meeting. Earlier this week, he discussed the outlines of a peace deal with Russian President Vladimir Putin, who also expressed optimism about the chances of reaching agreement.
For all the upbeat assessments, however, NATO Secretary-General Anders Fogh Rasmussen was skeptical of Russian motives. "What counts is what is actually happening on the ground, so it remains to be seen what it is, and I have to say that previously we have seen similar statements and initiatives and they have been a smoke screen for continued Russian destabilization of the situation in Ukraine," he said.
Since mid-April, Moscow-backed separatists have been fighting government troops in a conflict the U.N. estimates has killed nearly 2,600 people. On Thursday, a NATO military officer told The Associated Press the ranks of Russian soldiers directly involved in the conflict have grown.
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