BRUSSELS, August 23. /TASS/. The North-Atlantic Alliance has confirmed receiving an invitation for its experts to monitor the West-2017 Russia-Belarus military drills, but voiced discontent over the format of observation.

"Belarus has invited military liaison missions to attend distinguished visitors' days [during the exercises] on its territory. NATO will send two experts to attend," a NATO official said on Wednesday.

"However, this is not the same as observation as set out in the Vienna Document [on Confidence and Security-Building Measures]. We regret that neither Russia nor Belarus has applied the Vienna Document transparency measures to West-2017, in line with the rules agreed by all OSCE states," he said.

According to the alliance, the Vienna Document transparency measures envisage "briefings on the scenario and progress, opportunities to talk to individual soldiers about the exercise, and overflights of the exercise."

"Russia and Belarus are instead choosing a selective approach that falls short. Such avoidance of mandatory transparency raises questions," the official said.

The West-2017 military drills, scheduled to take place at six training ranges in Russia and Belarus on September 14-20, will involve around 13,000 troops (with around 10,200 of them deployed to Belarus) and nearly 680 pieces of military hardware.