NHK has learned that eight Russian officials may leave Japan as early as on Wednesday, following Tokyo's decision to expel them.

The Japanese government announced on April 8 the expulsion of the officials from the Russian embassy and trade representative office in the country.

Informed sources say the Russians are believed to have mainly engaged in intelligence gathering.

The sources say the eight are expected to board a plane chartered by Russia, and leave Tokyo's Haneda Airport at around noon on Wednesday.

It is extremely rare for Japan to expel multiple foreign diplomats or other officials. Russia is likely to take countermeasures, but the details are not yet known.