Warring parties in Ukraine meet on Friday to try to find a lasting solution to a brutal conflict that has killed around 3,000 people and stoked Western alarm about Russia's territorial ambitions.
The talks take place in Minsk two weeks since a fragile European-brokered ceasefire aimed at halting five months of bloodshed was agreed in the Belarussian capital with Moscow, Kiev and pro-Russian separatist leaders.
Overall, the truce has dramatically scaled back the fighting across industrial eastern Ukraine, although sometimes deadly shelling and gunfire is reported almost daily around the flashpoint city of Donetsk.
With the crisis at a potentially pivotal point, US President Barack Obama hosted Ukrainian leader Petro Poroshenko at the White House Thursday, with both condemning Russian "aggression".
But the meeting underscored the limits of US support for Kiev in the most serious confrontation between Moscow and the West since the Cold War.
- 'Blankets' can't win wars -
Poroshenko sat side-by-side with Obama in the Oval Office and drew multiple standing ovations from lawmakers in a ceremonial joint meeting of both houses of Congress.
But Poroshenko's appeal for NATO to grant Ukraine non-member ally status and for the shipment of weapons to help bolster its defences were rebuffed, despite his warning that non-lethal aid like "blankets" can't win wars.
Poroshenko told Congress that what he called Russian-backed proxy wars must be contained.
"If they are not stopped now, they will cross European borders and spread throughout the globe," he said.
"I urge you not to let Ukraine stand alone."
Just hours before his speech, Kiev accused Moscow of advancing 4,000 troops and weaponry based in annexed Crimea to the border with mainland Ukraine, further rattling nerves.
The US leader condemned Russian "aggression" in Crimea and eastern Ukraine, which he said was designed to undermine the country's territorial integrity and Poroshenko's efforts to introduce reforms to fix an economy on the brink of bankruptcy.
But his administration will not send arms to bolster Ukraine's armed forces, which in the days before the truce suffered major battleground defeats by rebels apparently backed by Russian elite troops.
Instead, a senior US official said Washington would offer Ukraine another $46 million in non-lethal aid.
And on Friday, Poland -- which has nervously watched Russia's actions across the border -- also said it would not send arms or otherwise get involved in the conflict.
The United States along with the European Union has hit Russia with a series of sanctions over its actions in Ukraine, the latest package targeting its major financial, energy and defence companies.
But in a bid to ease another dispute, the EU said it would hold fresh talks with Russia and Ukraine on September 26 to thrash out a deal on gas deliveries, with fears of a disruption to supplies during the winter months.
The conflict has already wreaked havoc on Ukraine's economy, with growth set to shrink nine percent this year.
- 'He was gone' -
Although the ceasefire has largely held, shelling has rocked the main insurgent stronghold of Donetsk almost every night.
Donetsk city council reported the death of one civilian Thursday, while the Ukrainian military said two soldiers had been killed over the past 24 hours and another six were missing.
"We don't know (what happened). I went to bed and he was watching television," said Lubov Zikova, whose husband Vladimir Zikov was killed.
"There was a huge explosion and everything fell on me. When I got out from there I was calling to him, but he didn't answer. He was gone."
Since the ceasefire, a total of 34 civilians and servicemen have been killed but there is no information on rebel casualties.
UN figures show that almost 2,900 people have lost their lives since the separatists unleashed their uprising against Kiev in April.
Poroshenko was in Washington two days after the parliament in Kiev ratified a historic pact with the EU in a further sign of his determination to take the former Soviet nation on a Western path.
And in further legislation that will be crucial in shaping the country's future, lawmakers offered three years of self-rule to the east.
The autonomy move was hailed by Russia but greeted with a mixed response by separatist leaders and nationalist leaders in Kiev who fear Ukraine is capitulating to Moscow.