The Collective Security Treaty Organization (CSTO, Russian: Организация Договора о коллективной безопасности (ОДКБ), romanized: Organizacija dogovora o kollektivnoj bezopasnosti (ODKB)) is an intergovernmental military alliance in Eurasia consisting of six post-Soviet states: Armenia,[note 1] Belarus, Kazakhstan, Kyrgyzstan, Russia, and Tajikistan.

[8] The Collective Security Treaty Organization (CSTO) maintains a peacekeeping force that has been deployed to areas of conflict, including Tajikistan and Kyrgyzstan.

[10] On 4 February 2009, an agreement to create the Collective Rapid Reaction Force (KSOR) (Russian: Коллекти́вные си́лы операти́вного реаги́рования (КСОР)) was reached by five of the seven members, with plans finalized on 14 June.

The force is intended to be used to repulse military aggression, conduct anti-terrorist operations, fight transnational crime and drug trafficking, and neutralize the effects of natural disasters.

On 3 August 2009, the Ministry of Foreign Affairs of Uzbekistan criticized plans by Russia to establish a military base in southern Kyrgyzstan for the CSTO rapid reaction force, stating, The implementation of such projects on complex and unpredictable territory, where the borders of three Central Asian republics directly converge, may give impetus to the strengthening of militarization processes and initiate all kinds of nationalistic confrontations.

At the same time, Uzbekistan joined the GUAM group, established in 1997 by Georgia, Ukraine, Azerbaijan, and Moldova, and largely seen as intending to counter Russian influence in the region.

[14] The CSTO was founded in 2002 when the six member states agreed to create the Collective Security Treaty Organization as a military alliance.

"[25] During a trip to Ukraine to extend Russia's lease of the Crimean port Sevastopol in return for discounted natural gas supplies, Russian President Dmitry Medvedev was asked about whether Belarus could expect a similar deal and responded: "Real partnership is one thing and a declaration of intentions is another; reaching agreement on working seriously, meeting each other halfway, helping each other is one thing and making decisions about granting permanent residence to people who have lost their job is another."

[27] Subsequently, the Russian television channel NTV, run by Gazprom, aired a documentary film which compared Lukashenko to Bakiyev.

[28] Then the Russian President's foreign policy adviser Sergei Prikhodko threatened to publish the transcript of a CSTO meeting where Lukashenko said that his administration would recognize Abkhazian and South Ossetian independence.

[32] Later, however, Bordyuzha admitted that the CSTO response may have been inadequate and claimed that "foreign mercenaries" provoked the Kyrgyz violence against ethnic Uzbek minorities.

[35] The CSTO was unable to agree on providing military assistance to Kyrgyzstan at a meeting in Yerevan, Armenia, which was attended by Roza Otunbayeva as well as Alexander Lukashenko.

[42] Thousands of Afghans, including police and government troops, fled to Tajikistan after Taliban insurgents took control of many parts of Afghanistan.

[48] The lack of Russian support during the conflict prompted a national debate in Armenia, as an increasing percentage of the population indicated doubt as to whether it is beneficial to continue CSTO membership, calling for realignment of the state with NATO instead.

[49] This coincided with a visit from Speaker of the United States House of Representatives Nancy Pelosi to Yerevan on 17 September 2022, largely seen as an effort to reorient the security alliance structure of Armenia.

With the leaders of all member states and CSTO Secretary General Stanislav Zas in attendance, the meeting was chaired by Armenian Prime Minister Nikol Pashinyan, who concurred with the report presented by the Secretary General while also reiterating the importance for a clear political assessment of Azerbaijani aggression and a roadmap for the restoration of Armenian territorial integrity.

[57] Meanwhile, during the meeting in Yerevan, large groups of protestors gathered and called for the withdrawal of Armenia from the CSTO and for the country to develop closer relations with the United States and the West.

[59] The diplomatic friction continued into January 2023, after Pashinyan refused to hold common military drills, because the organization did not unequivocally condemn Azerbaijan over its perceived aggression.

[60] In response, Dmitry Peskov, the Press Secretary of the President of Russia, stated that Armenia remains a very close ally and promised to continue the dialogue.

[61] To mend their ties, Sergey Lavrov offered the deployment of a CSTO mission along the Armenia-Azerbaijan border on 2 February 2023 within one or two days, "if our Armenian allies, friends are still interested in it like before".

[64] On 3 September 2023, during an interview, Armenian prime minister Nikol Pashinyan stated that it was a strategic mistake for Armenia to solely rely on Russia to guarantee its security.

Pashinyan stated, "Moscow has been unable to deliver and is in the process of winding down its role in the wider South Caucasus region" and "the Russian Federation cannot meet Armenia's security needs.

[66] Armenia declined participating in military exercises at the CIS summit in Kyrgyzstan in October 2023 and asked for Russian peacekeeping forces to return to Russia.

Pashinyan stated, "We have now in practical terms frozen our participation in this treaty" and "membership of the CSTO was under review" during a live broadcast interview.

Responding to Pashinyan's remarks, Dmitri Peskov stated that the CSTO charter does not include provisions for a "frozen membership" status.

[71] On 8 May 2024, Armenia announced it had stopped making financial contributions to the CSTO,[72] leading Russia to state that it was still obligated to pay its membership dues.

The member states adopted measures to counter cyber security threats and information technology crimes in a Foreign Ministers Council meeting in Minsk, Belarus.