Tashkent has sent a note of the notice of suspension of Uzbekistan's membership in the CSTO, a spokesman for the Collective Security Treaty Organisation, Vladimir Zaynetdinov, told Ria Novosti.
"At the moment, the CSTO experts are assessing documents received by the Secretariat, holding their due diligence, and the report of the President of the CSTO member states is being prepared," he said.
He did not specify reasons for such a decision of Tashkent.
Uzbekistan has already suspended its membership in CSTO - in 1999 Tashkent refused to renew the treaty, but in August 2006, Uzbekistan has restored membership in the CSTO.