- What is it?:
- The CSTO is a Russia-led military alliance of seven former Soviet states that was created in 2002.
- It has been described by political scientists as the Eurasian counterpart of NATO, which has 29 member states, while the CSTO has just six.
- Aim: Its purpose is to ensure the collective defence of any member that faces external aggression.
- Members: Armenia, Belarus, Kazakhstan, Kyrgyzstan, the Russian Federation and Tajikistan. Afghanistan and Serbia hold observer status in the CSTO.