NATO Leaders Gather at Welsh Golf Resort as Pro-Russia Forces Approach Ukrainian Port City

As western leaders gathered at a golf resort in Newport, Wales on Thursday to discuss bolstering Kiev's beleaguered defenses, clouds of black smoke rose just a few miles east of Mariupol as pro-Russia forces launched a fresh assault in Ukraine's southeast.

Standing at the eastern most checkpoint of the city a panicked fighter from the pro-Kiev Azov Battalion told VICE News they had been pushed back from their positions in Shyrokyne — a village just six miles east of the outskirts of Mariupol — on Thursday afternoon after coming under sustained mortar fire. "After three hours we were given the order to retreat. Our positions were hit very hard and very accurately," he added.

Just minutes later a round of incoming grad rocket fire that landed a mile or so away caused some fighters to run for the trenches, while others jumped in their cars and drove away in the opposite direction.

Pro-Russian forces advanced a new front in Ukraine's southeast 10 days ago pushing down from the Novoazovsk border crossing with Russia, but halted their advance several miles shy of Mariupol, a militarily significant port city of nearly half a million people.

Speaking at the sidelines of the NATO summit earlier in the day, Ukraine's President Petro Poroshenko said he hoped that a "bilateral ceasefire" would start at 2 pm local time on Friday, but emphasized that he would only give the order to Ukrainian armed forces to lay down their weapons if a meeting scheduled for Friday in Minsk goes ahead as planned. Representatives from Ukraine, Russia, the pro-Russian rebels, and the Organization for Security and Co-operation in Europe are expected to attend the conference in the Belarusian capital.

The Ukrainian president's announcement follows a telephone conversation with his Russian counterpart, Vladimir Putin, who yesterday proposed a seven-point peace plan which included the demand for militias to cease military advances in Donetsk and Luhansk and for pro-Kiev forces to withdraw to a distance that would exclude the possibility of shelling settlements.

Rebel leaders have also expressed a willingness to find a political solution to end the bloodshed. In a statement released today, Prime Minister of the so-called Donetsk People's Republic Alexander Zakharchenko said his men would also order a ceasefire, provided that Kiev's representatives signed up to a peace plan at the Minsk meeting.

Critics, however, have expressed skepticism that any ceasefire deal could simply be used as an opportunity by both sides to re-arm and re-position. Previous localized deals to hold fire have failed after both sides accused the other of violating agreements.

According to the latest United Nations figures, at least 2,600 people have been killed in the east Ukraine conflict, with more than half the casualties incurred between mid-July and mid-August. A further 1 million people are believed to have fled the region due to the fighting.

Alongside militant terrorist group the Islamic State, the Ukraine conflict is at the top of the two-day NATO summit's agenda where western officials will discuss how to bolster Kiev's beleaguered defenses against its increasingly hostile neighbor.

Setting the tone for the meeting,  NATO's Secretary-General Anders Fogh Rasmussen said this morning that the summit was taking place in a "dramatically changed security environment." He directly accused Russia of "attacking Ukraine."

"We are still witnessing, unfortunately, Russian involvement in destabilizing the situation in eastern Ukraine," Rasmussen told journalists at a briefing ahead of the summit's official launch.

The host of the summit, Britain's Prime Minister David Cameron, said Ukraine knew it had the support of the west. He stopped short of lending his backing to arming Ukraine, saying that support should be limited to financial, legal, technical and non-lethal assistance.

"I don't think we should be arming them directly, we need a military de-escalation in Ukraine not an escalation," Cameron said in an interview this morning.

NATO has previously released satellite images purporting to show the movement of military vehicles and says that Russia now has more than 1,000 soldiers operating inside its neighbor's borders. The Kremlin denies the allegations despite swathes of evidence to the contrary, including families in Russia who say their relatives serving in the Russian military were killed fighting in covert operations in Ukraine.

Earlier this year NATO suspended its cooperation with Moscow after Russia annexed Ukraine's southeast peninsula, Crimea, following a Putin-backed putsch.

Backed by a growing number of Russian soldiers the rebel forces fighting in Ukraine's east have made substantial advances in the last 10 days pushing a new front in the country's southeast and winning decisive victories over government forces around the rebels' stronghold cities Donetsk and Luhansk.

The scale of the loss incurred during a recent defeat in Iloviask, where at least sixty-eight Ukrainian military vehicles were hit by shelling as they attempted to retreat from the town, shows just how much pressure Kiev's forces are now under.

Visiting the frontline trenches in Mariupol's east today, Sergey Taruta, the Kiev-appointed Governor of Donetsk, said that the city of nearly 1 million people was "well protected."

But, Alexy, a Commander of Dnipro 1 — one of the volunteer battalions charged with defending the city — told VICE News they were far from prepared. "If they use tanks, I don't know how long we can hold" he said. When asked if more reinforcements were on their way the commander just laughed. "There aren't any military units left that want come."

Follow Harriet Salem on Twitter: @HarrietSalem