Muneo Suzuki, one of the JIP deputies in the Consultative Assembly, visited Russia last week and met with Russian Deputy Foreign Minister Andrey Rudenko.
Muneo was officially expelled from the party in line with the decision of the JIP Presidium, after the party's Ethics Committee stated that he displayed "undisciplined behavior".
The decision was influenced by Muneo's overseas visit without prior notification to the party and his "controversial statements" during this visit.
Russian media footage of the visit showed Muneo saying that he was "100 percent sure that Russia will win in the aggression against Ukraine".
The 75-year-old Muneo's visit was recorded as the first visit of a Japanese lawmaker to Russia after the Russia-Ukraine crisis that began in February 2022.