Crisis-hit Ukraine won a vital reprieve from Russia on Monday when Moscow pushed back a possible cut in gas shipments, which would also impact parts of Europe, until next week.
Russia's surprise decision came hours before the two sides were to lock horns in Brussels over a price dispute that emerged when Moscow cancelled the discounts it awarded the pro-Kremlin regime which was ousted in February street protests.
Moscow had threatened to halt all shipments to Ukraine -- a vital gas transit nation -- from Wednesday in a repetition of interruptions that also hurt swathes of Europe in 2006 and 2009.
Ukraine was due to receive another vital boost as it battles a bloody separatist insurgency along its Russian border with a visit to Kiev by US Assistant Secretary of Defence Derek Chollet.
But the seven-week campaign continued unabated when pro-Russian gunmen wounded several Ukrainian border guards in the eastern rust belt district of Lugansk in an overnight raid.
- Russia 'welcomes' Ukraine payment -
Russia's state-run gas giant Gazprom -- long accused of acting as the Kremlin's political enforcer against neighbours seeking closer ties to the West -- said it "welcomed" Ukraine's decision to transfer a $786-million payment to partially cover its debts.
"We welcome Ukraine starting to pay back its debt and postpone the pre-payment regime until June 9," Gazprom chief executive Alexei Miller said in a statement."
Ukraine branded Gazprom's decision to nearly double its gas price a form of "economic aggression" and balked at Russia's demand for advance payments for deliveries starting in June.
Gazprom had said it would halt all shipments to Ukraine unless it paid for June deliveries by Monday night.
Russian gas transits through Ukraine to supply about 15 percent of European needs and a top European Union envoy is now urgently seeking a compromise that could save 18 member states from seeing their deliveries start dwindling this week.
Gazprom hinted on Monday that it might delay the gas supply cut even further if Ukraine starts making partial payments for April and May deliveries.
Ukraine's Naftogaz state energy company for its part said that it had sent Gazprom an additional agreement to their disputed 2009 contract that stipulates a lower gas price.
"The additional agreement provides for changes to (2009) contract conditions where they concern the price," Naftogaz said in a statement.
Gazprom says it is ready to discuss a lower price and analysts believe that a compromise is in sight because Russia would prefer to avoid complicating its relations with Europe still further.
- US military boost -
Ukraine's president-elect Petro Poroshenko -- a charismatic confectionery tycoon who scored a crushing victory in a May 25 election and refuses to recognise Russia's March annexation of Crimea -- is seeking a closer Western military alliance that could protect his splintered country's sovereignty.
The visit by Pentagon's second-ranked commander comes ahead of Poroshenko's first meeting on Wednesday in Warsaw with US President Barack Obama.
Ukraine and the Soviet satellites of eastern Europe are anxious about the impact of a big speech Obama gave last week in which he put American diplomacy above military might in confronting threats such as that of Russia's expansion.
But US officials insist that Washington's commitment to Ukraine remained strong.
"I am certain that as soon as president-elect Poroshenko is sworn into office, we will begin discussions about our future cooperation on security and defence," US Ambassador Geoffrey Pyatt told Kiev's Dzerkalo Tyzhnia newspaper.
- Elusive Putin meeting -
Russian President Vladimir Putin spelt out the threat of an outright invasion of Ukraine when he sought and won parliament's authorisation on March 1 to use any means necessary to "protect" his compatriots living across the border.
But the drumbeats of war began fading last month when Putin surprised many by suddenly softening his tone.
The Russian leader advised Ukraine's eastern Lugansk and Donetsk regions against holding May 11 independence referendums that went ahead anyway but which he then refused to recognise as binding.
Putin also promised to "respect" the outcome of Ukraine's own election and began pulling back the 40,000 troops he had parked just inside Russia's border in an ominous show of strength that touched off near-panic in Kiev.
Western diplomats remain sceptical about the sincerity of Putin's restraint.
But they agree that it provides a welcome opening for Poroshenko as he tries to arrange the first meeting by a Ukrainian leader with Putin since the seizure of Crimea sparked he worst East-West crisis since the Cold War.