Earlier in the day, a number of Kazakh media reported that Armenian Prime Minister Nikol Pashinyan was allegedly holding consultations with Kazakh officials on their countries' possible withdrawal from the organization.
"This information does not correspond to the reality," the spokesman told a press conference.
The developments came after Gunther Fehlinger, the chair of the European Committee for NATO Enlargement, on September 4 urged Pashinyan to bring his country into the US-led military alliance.
Both Armenia and Kazakhstan are members of the CSTO, which also includes Russia, Belarus, Kyrgyzstan and Tajikistan. In June, Armenian Security Council Secretary Armen Grigoryan said membership in the CSTO created "certain problems" for Yerevan, although they did not limit cooperation with other nations.