Not really. Southern Kuril islands were negotiated by USSR with USA and UK as a price for USSR joining the war against Japan during WW2 after Germany was defeat

Not really. Southern Kuril islands were negotiated by USSR with USA and UK as a price for USSR joining the war against Japan during WW2 after Germany was defeated. But after WW2 occupied Japan under the pressure of USA refused to sign a peace treaty with USSR and regulate territorial dispute. Russia and Japan were in talks about peaceful resolving Southern Kuril issues for decades, but the main obstacle is that Japan is still an occupied nation with USA military bases stationed there. After USA pressured Japan to sanction Russia and send military support to Ukraine, all talks about Kurils were terminated.