Though Ukraine has seen its fair share of instability over the past few months, the country is bracing for what could be another sharp spike in volatility this weekend. Friday marks the start of Victory Day, a holiday commemorating the capitulation of Nazi Germany to the Soviet Union in World War II. This period marks a high point in Soviet nostalgia and Russian nationalism, and in Ukraine — and perhaps elsewhere in former Soviet territory — it could lead to more violence from both pro- and anti-Russian factions.

Sensing the inherent danger of such provocations, administration authorities in Kiev have canceled a Victory Day military parade in the city. Instead, the holiday will be marked by a prayer service for the victims of World War II, as well as wreath-laying ceremonies. The government is clearly worried about the potential for violence and clashes to occur, as they did when demonstrations in Maidan Square precipitated confrontations between protesters and police, eventually leading to the ouster of former Ukrainian President Viktor Yanukovich in February.

The plans to tone down the celebration of past military achievements come at a time when Ukrainian forces are active in the country. Counterterrorism operations continue in eastern Ukraine, with clashes between Ukrainian security forces and pro-Russian separatists occurring on a regular basis, particularly in Kramatorsk and separatist strongholds like Slovyansk. These operations have had limited success, however, as separatists continue to capture and occupy regional administration and security buildings throughout Donetsk oblast, as well as in neighboring Luhansk.

It is these two regions that have the greatest risk of seeing heightened violence this weekend, as separatists in each plan to hold referendums May 11 on declaring outright independence from Ukraine. It is unclear how much support or participation these unofficial referendums will garner, given that they are being organized by the likes of the Donetsk People's Republic and the Luhansk People's Republic, groups that until recent weeks had not even been formed. The membership of these groups is unclear, and likely to be no more than a few hundred people. Even their leaders are not well known. Recent polls also show that most people living within the Donetsk and Luhansk oblasts do not share the separatist sentiments of the People's Republics.

Still, the talk of referendums has been enough to provoke significant concern from authorities in Kiev. Ukraine is scheduled to hold presidential elections May 25, and the separatist activity in the eastern regions and potentially in other cities like Odessa threatens to significantly compromise, if not altogether derail, such a vote from being held. This is likely Russia's intention; Moscow considers the government in Kiev to be illegitimate and is influencing or at the very least supporting the pro-Russian groups as a way to undermine the Ukrainian government.

However, in an apparent about-face, Russian President Vladimir Putin on May 7 called on the separatists to postpone these referendums in order to give the negotiation process between Russia, Ukraine and the West a chance to work. Putin also referred to Ukraine's presidential elections as "a move in the right direction," seemingly contradicting several Russian officials who have repeatedly spoken out against the vote. However, Putin did caveat his statements by saying that Ukraine should cease all military operations in the east and implement constitutional reforms on decentralization before the presidential election is held.

While such statements were met with cautious optimism from the West, separatists in Donetsk and Luhansk announced Thursday that they would hold the referendums this weekend as scheduled. This either shows that Russia does not have as much control over the pro-Russian separatist groups in the east as many believe, or that Putin was attempting to show a pragmatic face in an effort to convince Ukraine to cease its military operations through diplomacy rather than through force, while in reality still maintaining influence over these groups. Either way, the offer has not had much of an impact on the ground just as April's Geneva agreement to de-escalate tensions in the east never achieved its desired result, with groups on both sides refusing to lay down their arms.

Therefore, with political talks showing little in terms of tangible results, the competition between Russia and the West over Ukraine will continue to play out on the ground and through the various proxy groups that both sides support. Pro-Russian groups — not only in Ukraine, but in countries like Moldova and Latvia — may use this weekend as an opportunity to show that despite efforts by their respective governments to strengthen ties to the West, their orientation to Russia must also be taken into account. In this way, a day commemorating a war that ended almost 70 years ago shows old patriotism to be very much alive and influential today.