UkraineREUTERS/Gleb GaranichA Ukrainian Mi-24 helicopter gunship flies above a military base in the eastern Ukrainian town of Kramatorsk August 27, 2014.

Russian troops fighting on the side of separatists in Ukraine are advancing in the southeast region of the country, Ukraine President Petro Poroshenko said on Thursday.

“I have made a decision to cancel my working visit to the Republic of Turkey due to sharp aggravation of the situation in Donetsk region, particularly in Amvrosiivka and Starobeshevo, as Russian troops were brought into Ukraine,” the Poroshenko said.

The new front opened in Amvrosiivka and Starobeshevo opens a pathway to Crimea, which Russia annexed with special forces troops in March.

The fear is that Russia is attempting to create a land link between Russia and the strategic peninsula.

Russian troops are leading a separatist counteroffensive in the east, bringing in tanks and using artillery from inside Ukrainian territory.

“This is what happened: they crossed the border, took up positions, and started shooting,” Sgt. Aleksei Panko said after telling The Times that about 60 armoured vehicles crossed the border near the town of Novoazovsk. “This is now a war with Russia.”

Geopolitical expert Ian Bremmer concurs:

Novoazovsk, south of Amvrosiivka and Starobeshevo, is on the highway linking Russia to the Ukrainian port of Mariupol and onto Crimea. Ukraine’s military said Russian troops have taken control of Novoazovsk and several other settlements in the south of Donetsk region.

UKRAINEREUTERSA look at the fighting in Ukraine’s southeast, where until this week Ukrainian forces were re-taking territory very quickly over the summer.

A Russian-backed rebel leader admitted that at least 3,000-4,000 Russian troops are fighting inside Ukraine.

“Current servicemen are also fighting in our ranks, as they came to us to struggle for our freedom instead of their vacations,” Prime Minister of the self-proclaimed Donetsk People’s Republic (DPR) Alexander Zakharchenko told Russian media. “This is characteristic only for Russians.”

Ukrainian Prime Minister has called for an emergency UN Security Council meeting to deal with the issue of Russian troops in Ukraine, although Russia sits on the council and could veto any proposal that arose.

“The Russian military’s use of artillery from locations within Ukraine is of special concern to Western military officials, who say Russian artillery has already been used to shell Ukrainian forces near Luhansk,” Andrew Kramer and Michael Gordon of The Time reported on Wednesday. “And along with the antiaircraft systems operated by separatists or Russian forces inside Ukraine, the artillery has the potential to alter the balance of power in the struggle for control of eastern Ukraine.”

Russian Armoured Personnel CarrierStringer ./REUTERSRussian servicemen drive armoured personnel carriers on the outskirts of the city of Belgorod near the Russian-Ukrainian border, April 25, 2014

On Tuesday, dozens of heavily armed strangers with Russian accents and military gear without insignias appeared in an eastern Ukrainian village east of the rebel stronghold of Donetsk and set up a roadblock.

“The people at the new checkpoint, they were polite military men wearing green. Definitely not Ukrainian. They’re definitely not from around here,” one man told Reuters.

The “green men” are a reminder of the Russian special forces that were used to annex the Ukrainian peninsula of Crimea.

The Times noted that Putin, who was in Belarus this week for talks with Ukrainian and European leaders, may be “calculating that Moscow could intervene in eastern Ukraine with conventional Russian forces without risking further Western economic sanctions.”

Putin poroshenkoREUTERS/Sergei Bondarenko/Kazakh Presidential Office/PoolRussian President Vladimir Putin (L) shakes hands with his Ukrainian counterpart Petro Poroshenko, as Kazakh President Nursultan Nazarbayev (C) stands nearby, in Minsk August 26, 2014.

Here’s a look by province, and what else Russia would have to annex to create the land bridge:

Screen shot 2014 04 30 at 10.25.58 am


And here’s the fighting as of today, according to Ukraine’s military:

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