Uzbekistan, which was a charter member of both the Collective Security Treaty Organizaton (CSTO) and the Shanghai Cooperation Organization (SCO) disrupted both organizations this month. Two weeks ago, the SCO held its annual military exercises. Uzbekistan has traditionally declined to participate in this event, but this year it went further when it forbade Kazakh military forces from transiting its territory or airspace to the exercise location in Tajikistan.
Then, this week, Uzbekistan announced that it was suspending its membership in the CSTO. Uzbekistan is also a partner in the third competing politico-military organization in Eurasia, the NATO sponsored Partnership for Peace. The Uzbeks have not done anything to upset that apple cart this month; indeed, at the beginning of the month, they signed a deal with NATO to allow the transit of NATO equipment through their nation as the Afghanistan pullout picks up speed.
As a reminder, here are the competing alliance structures in the Central Asia region: