MOSCOW - Seven former Soviet republics, which form the Collective Security Treaty Organization (CSTO), are holding joint strategic military exercises code-named Center 2011, the Russian Defense Ministry said on Monday.

According to the ministry, the drills start on Monday and are due to take place in Russia, Kazakhstan, Tajikistan and Kyrgyzstan.

The CSTO, whose headquarters are located in Moscow, was established in October 2002 as an intergovernmental military alliance. It groups seven members -- Armenia, Belarus, Kazakhstan, Kyrgyzstan, Russia, Tajikistan and Uzbekistan.

The wargame will be held under the leadership of Russian General Staff Chief Army General, the ministry said, adding that the active phase of the drills will last until September 26.

The ministry also stressed the drills will be a key indicator of the Russian armed forces' military training level as part of an ongoing military reform. Russian President Dmitry Medvedev will supervise the event.