Deal Establishes 'Buffer Zone' Between Ukrainian Troops and Rebels

A fragile ceasefire in eastern Ukraine was ostensibly strengthened early Saturday morning after negotiators in Minsk, Belarus agreed to create a buffer zone 19 miles wide between territory held by Ukrainian troops and pro-Russian separatists. Both the government forces and rebels also agreed to a deescalation that includes the removal of heavy weapons and foreign troops from the conflict zone.

The agreement to establish the buffer zone — which is essentially a demilitarized area nine miles wide on either side of the front lines — was reached after several hours of negotiations overnight. It is scheduled take effect within 24 hours.

The Minsk deal seeks to bolster an earlier September 5 ceasefire signed by representatives from Kiev, Russia, and the Moscow-backed rebels.

Reports and videos of apparent ceasefire violations have surfaced often in the weeks following the deal, though monitors from the Organization for Security and Cooperation in Europe (OSCE) have maintained that the accord remains intact.

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Former Ukrainian president Leonid Kuchma, who represented Kiev in the most recent talks, said the demilitarized zone would also ban warplanes flying over the area and prohibit minefields.

The pact, signed by the self-proclaimed leaders of the rebel-held cities Donetsk and Luhansk, and Russian ambassador to the Ukraine Mikhail Zurabov, also requires both camps to immediately withdraw "foreign mercenaries."

Last month, Ukraine accused Russia of covertly sending up to 1,000 paramilitary forces and heavy weapons across its porous border to help the separatists fight Ukrainian government forces.

Moscow has routinely denied these claims, saying instead that those fighting alongside the rebels are civilians acting of their own volition.

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But, after signing off on the new buffer zone, Russia's Zurabov, changed his tune, acknowledging that there appeared to be "mercenaries are present on both sides."

OSCE envoy Heidi Tagliavini said that monitors will continue to watch the situation across the region, including in and around the new buffer zone.

The Russian-speaking industrial regions of Donestsk and Luhansk, together with the port city of Mariupol, have seen the heaviest clashes since the initial truce went into effect earlier this month.

At least 20 rebels and one Ukrainian fighter were killed in the area over the last 24 hours, a Ukrainian national security council spokesman told the Associated Press on Saturday.

In Donetsk, powerful explosions were heard just outside the city Saturday near a state-owned chemical factory, according to the Donetsk Mayor's Office. A video later showed a thick plume of smoke and fire rising high above the building.

A huge fire was reported at a factory in Donetsk on September 20. A cause for the fire is not yet known. A number of explosions were also reported at the site. This video is described as showing the fire outside Donetsk.

Officials have not yet determined the official cause of the fire.

The latest Minsk deal could help solidify the truce, though many remain skeptical that a ceasefire will hold amid continued provocations from both sides. The September 5 agreement also failed to address the future administration of Ukraine's rebel-held areas.

Separatists have been seeking to secede from the Ukraine since tensions boiled over following the ousting of former pro-Russian president Viktor Yanukovych in February. Russia's annexation of Crimea in March and indirect support of the movement triggered five months of fighting that has left more than 3,000 people dead.

The deteriorating situation in Ukraine has sparked fears of emboldened territorial ambitions by Russia, and caused the steepest drop in East-West relations since the Cold War, prompting economic sanctions from both Washington and Moscow.

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The September 5 peace accord was signed hours after NATO approved setting up an Eastern European-based rapid-response force to counter further Russian aggression in the region.

Ukraine's new president, Petro Poroshenko, cornered after months of fighting that pushed back and depleted government forces, has offered amnesty to some pro-Russian separatists and made concessions to the rebels for limited administration of regions under their control in its wake.

A law passed by the Ukrainian government this week ensured further freedoms that would allow the separatists to hold local elections and form police forces.

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Follow Liz Fields on Twitter: @lianzifields