From June 2 to 4, the Republic of Belarus hosted the second staff talks on the organization and conduct of the CSTO Peacekeeping Forces command-and-staff exercise “Indestructible Brotherhood 2026” and the special exercise “Barrier 2026” involving the CSTO Joint CBRN Protection and Medical Support Formation.

On June 3, 2026, a regular meeting of the CSTO Council of Defense Ministers (CDM) was held at the Patriot Central Park of the Russian Ministry of Defense under the chairmanship of the Russian side. The meeting was attended by CSTO Secretary General Talatbek Masadykov and Chief of the CSTO Joint Staff Andrey Serdyukov.

From June 1 to 3, Saratov (Russian Federation) is hosting a series of events involving the member states of the Collective Security Treaty Organization aimed at strengthening the collective response system to biological threats.

On June 1, 2026, consultations at the deputy foreign minister level of the CSTO member states were held in Moscow.

On May 28, 2026, CSTO Secretary General Talatbek Masadykov took part in the International Security Forum held under the auspices of the Security Council of the Russian Federation. More than 150 delegations from 120 countries participated in the event.