BRUSSELS (AP) — NATO says it will send three experts to observe military exercises involving Russian and Belarus troops next month but wants the two countries to allow broader monitoring of the war games.

Russia and Belarus say the Zapad 2017 exercise will involve less than 13,000 troops. Under international rules, the two should allow wider access to monitors if troop numbers exceed that figure.

A NATO official said Wednesday that experts will attend "Visitors' Days" in Belarus and Russia, after they were invited to attend. The official's job description does not permit him to speak on the record.

He said international rules permit monitors to have "briefings on the exercise scenario and progress; opportunities to talk to individual soldiers about the exercise; and overflights of the exercise." Zapad starts on Sept. 14.