At the fall of the USSR, Coca-Cola should have bartered soda with Russia for the nukes. After all, the Cola Wars were heating up even as the Cold War looked to be ending, and Pepsi had a superior navy, bartered from the USSR with soda, and Coke could have used a nuclear deterent.

Have the CIA turn enough insiders that one of them succeeds in assassinating Putin after a propaganda campaign raising up an opposition party ready to take over in an election/coup (mixture of both really). Have a weak and friendly leader installed that exchanges nukes for population support and possibly brakes up Russia into several smaller states.

When the USSR broke up, Ukraine gave up its nukes in exchange for security guarantees (lot of good that has done them)