Summary Fighting has rumbled on around the city since it was retaken by Ukrainian forces in June
KIEV (AFP) - A strategic port of some 500,000 residents before the Ukraine crisis, Mariupol is the largest remaining government-held city in east Ukraine s conflict zone and seen as a likely target for any new pro-Russian rebel offensive.
Fighting has rumbled on around the city since it was retaken by Ukrainian forces in June, and Kiev has accused pro-Moscow forces of massing heavy weapons there despite a supposed ceasefire.
Here are the factors underlying its importance:
- Last government stronghold -
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Mariupol -- some 55 kilometres (35 miles) from the Russian border -- is the biggest city still in Kiev s hands in the conflict zone that includes the rebellion-hit Donetsk and Lugansk regions.
In June, Ukrainian forces retook the port from the loose control of pro-Russian separatists but it remained firmly in the sights of rebel leaders.
In September, rebel forces -- which Ukraine and the West said were spearheaded by Russian troops and armour -- reached the city s outskirts but stopped short of launching an all-out offensive to capture it.
Since then clashes have continued in outlying villages to the east. Ukraine accuses Russia of concentrating more forces there in preparation for a possible fresh attack.
- Industrial hub -
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Mariupol is dominated by two vast iron and steel enterprises owned by Ukraine s richest oligarch, Rinat Akhmetov.
The sprawling Ilyich plant -- the largest business in the region -- and the Azovstal factory together employ tens of thousands of people and is a key economic asset for anyone who holds the city.
While initially hedging his bets over the rebellion in his home region, Akhmetov eventually came out against the separatists.
- Access to sea -
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Capturing Mariupol would also give the rebels control of a major port on the Azov Sea coast.
Securing the vital link is seen as key to making any rebel-held regions self-sustainable in the long-term.
- Gateway to Crimea? -
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To many, the importance of Mariupol is that its capture would remove a key obstacle to creating a land corridor stretching from Russia s border with Ukraine to the Crimean peninsula, which Moscow annexed in March.
Russia currently has only a precarious ferry link to the region, which is essentially under an economic blockade by Ukraine. A $3.0 billion bridge project is not scheduled for completion until 2018.
However, the port city is still some 300 kilometres (200 miles) from Crimea, and pro-Russian forces would have to seize large swathes of territory that has so far been spared from the uprising.
- Risks too high? -
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Any attempt by the rebels to take Mariupol would represent a serious escalation in the conflict and a definitive end to an already tattered peace plan.
A battle for the city would likely prove to be among the bloodiest in Ukraine s 10-month-old conflict and spark a new round of tough Western sanctions against Moscow.
