The European Union on Tuesday decided to keep in place biting economic sanctions on Russia over its alleged backing of pro-Kremlin insurgents who have largely ignored a four-week Ukrainian truce.
The bloc's announcement came just moments before NATO reported the continued presence of "hundreds" of elite Russian soldiers in the war-torn former Soviet nation's separatist east.
The two Western alliances' continuing pressure on Russia -- already more isolated than at any point in Vladimir Putin's 15-year rule -- set an ominous tone to the launch of Ukraine's October 26 parliamentary election campaign.
EU spokeswoman Maja Kojicancic said member states saw "encouraging developments" in parts of the September 5 truce agreed by Moscow and Kiev.
But she stressed that other parts "need to be properly implemented" before sanctions could be eased.
Moscow's EU envoy Vladimir Chizhov was saying by Interfax as responding: "We will see how what our partners do next. But their behaviour up to now does not leave us inspired."
The Ukraine truce was reinforced with an agreement to create a 30-kilometre (18-mile) buffer zone that could make sure no further return to bloodshed in which more than 3,200 have lost their lives.
But a rare public attempt by a Russian military mission to convince the rebels to comply with the truce ended in seeming failure.
The Ukrainian military said militias on Monday launched a tank assault on a long-disputed airport outside the rebel stronghold of Donetsk in which a shell hit an armoured vehicle filled with government troops.
At least nine soldiers died in the strike and ensuing firefight. Local and Ukrainian state officials reported the death of five civilians by Tuesday evening.
The joint US and EU sanctions on Russia's largest banks and energy companies aim to cut off the Kremlin from its main sources of income and erode Putin's domestic support.
But the economic struggles have done little to slow Putin's seeming -- but denied -- ambition of keeping a permanent hold on Ukraine's Russian-speaking east and undermining Kiev's historic shift toward the West.
NATO on Tuesday said "hundreds of Russian troops, including special forces, still remain inside Ukraine" despite a "significant" recent withdrawal.
Moscow argues that any Russian soldiers in Ukraine went there while off duty and based on heartfelt political convictions rather than any orders from the Kremlin.
- Poroshenko's election test -
A promise by Ukrainian President Petro Poroshenko to grant temporary self-rule for territories under rebel control as long as they give up separatist ambitions has dominated political debate in the run-up to the parliamentary polls.
The pro-Western leader called the snap vote under pressure to sweep away factions that many see as complicit in the February shooting by police of 100 protesters in the final days of the ousted Kremlin-backed regime.
The Petro Poroshenko Bloc -- headed by the charismatic and hugely popular former boxing champ Vitali Klitschko -- is the early favourite to finish with the largest share of seats in the new and more powerful parliament.
But the Klitschko-Poroshenko alliance is unlikely to secure an outright majority in the 450-seat chamber.
And Poroshenko's chances of forging a coalition that could help make peace with Russia while securing a military and economic alliance with the West look somewhat remote.
Other main parties with a chance of making it into the new chamber represent either nationalist forces or new pro-Kremlin groups that refuse to accept Ukraine's rejection of its historic ties to Russia.
The anti-Kremlin contingent includes the People's Front group of Prime Minister Arseniy Yatsenyuk and parliament speaker Oleksandr Turchynov -- dubbed by Moscow as Ukraine's "party of war".
Also likely to make it are the Batkivshchyna (Fatherland) party of ex-premier Yulia Tymoshenko -- an opposition icon stained by corruption allegations -- and the Radical Party of the populist Oleg Lyashko.
Both oppose even a hint of compromise with the rebels. They also suggest that force may be needed to seize back the Black Sea peninsula of Crimea that Russian annexed in March.