“Zapad is a joint training exercise of Belarus and Russia, in regard to which we expect to see much greater transparency and their observance of international agreements both before and during the exercise,” Luik said according to remarks published on the website of the Ministry of Defence on Friday afternoon.

Russia had introduced its Zapad exercise only in the NATO-Russian Council, where it gave notice that altogether 7,000 military personnel from Belarus and 5,200 from Russia would take part in the Sept. 14-20 drills.

“Considering the experience and the scale of Russia’s exercises at the strategic level, Zapad 2017 and the additional exercises to be held parallel to it will be based on an anti-NATO attack scenario, in which up to 100,000 Russian soldiers and officers may take part, significantly more than officially announced,” Luik said.

Russia has decided to present the exercise at a single event at the Luga training ground on Sept. 18-19, to be held for the defense attachés accredited to Moscow. No invitations have been received by the Organization for Security and Cooperation in Europe (OSCE) to monitor the exercise.

Belarus has formally notified the OSCE that Zapad will be held on its territory on Sept. 14-20. In addition, Belarus, under the principle of voluntariness of the Vienna document, has invited two observers each from Estonia, Latvia, Lithuania, Norway, Poland, Ukraine and Sweden to take part in a program lasting from Sept. 16-20. Estonia has accepted the invitation.

Additionally, the Estonian defense attaché will participate in a Zapad-related program to be organized by the Belarusian ministry of defense on Sept. 19-21.

According to official information, 7,090 members of the armed forces of Belarus and 3,106 members of the armed forces of Russia, 138 main battle tanks, 232 armored vehicles, and 142 large-caliber weapons of indirect fire will take part in the exercise on the territory of Belarus, and up to 185 sorties of aircraft are planned.

According to the Estonian Defence Ministry, no specific information has been provided about the portion of the exercise to be held in Russia. In earlier years NATO on multiple occasions registered a splitting up of military exercises as well as non-reporting and underreporting by Russia. In addition, Russia has staged large-scale snap exercises, which under international rules can only be held as an exception.

In accordance with the Vienna document, OSCE member states must invite observers to military training exercises involving more than 13,000 personnel. Exercises involving at least 9,000 members of the armed forces must be announced at least 42 days prior to their start.