According to Stratfor, there are two indicators we are watching that could provoke responses by both sides: newly trained pro-Russian separatists rotating in, and NATO finally installing Force Integration Units into Eastern European countries along Russia's periphery.

February's agreement to halt hostilities between Ukraine and the Russian proxies has proved to be a cease-fire in name only. Meanwhile, the political dimension of the conflict has so far barred any definite resolution, and as long as a deep gulf separates Kyiv and its Western backers from Moscow and the militants over the future of Ukraine, the potential for further escalation on the battlefield remains. 

To basic issues divide the two sides. The first is the political status of the separatist regions. Ukraine wants to see separatists implement the Minsk agreements and lay down their arms before officials amend the Ukrainian Constitution to grant the eastern territories more autonomy. The separatists want constitutional changes first, and they want a role in determining those changes.

The second, deeper issue goes beyond Ukraine: the role of Russia as a regional power. For geopolitical reasons, Moscow sees the former Soviet Union as a sphere of influence in which it must have privileged interests. The West, and particularly the United States, wants to deny Russia that sphere, reads the report.

It is in Ukraine, where these frictions became so intense that they ignited into open warfare. Now, several factors are likely to prompt even more violence. One is the coming of warmer August weather, which will make it easier to mount combat operations. Another is the debate over Ukraine's constitutional reforms, with the rebels defying decentralization measures by the Ukrainian government and vowing to hold their own self-styled elections in October and November, a step Kyiv rejects. Yet another is Russia's frustration over sanctions, which the United States has increased and the Europeans have extended until the end of the year. Moscow may see no reason not to escalate the conflict on the battlefield if the West is offering only more threats.

But an even more concrete warning sign is the fact that the NATO Force Integration Units proposed last year are finally set to be established later this month. The presence of thesenew forward staging units in Eastern Europe, right on Russia's doorstep, could end up provoking Moscow.

All this does not mean, however, that Russia is willing or prepared to ramp up military operations to the point of a full-blown invasion. There are still too many constraints on Moscow, whether disastrous economic repercussions or the prospect of a corresponding military escalation on the part of the West if Russian troops moved into Ukraine or elsewhere in the former Soviet periphery. Each side is currently walking in some space between escalation and trying to keep control over that escalation without launching a full war. 

With meaningful progress in diplomatic negotiations so far sorely lacking, and with few positive signals out of the West at the moment, Russia may be considering sending its own message in eastern Ukraine in the next few weeks.