If Putin is to believed, then "...which other nuclear powers do not and will not possess." would seem to indicate they don't plan to sell it...
Surely you've been on the playground, where one kid tries to build envy in the other saying, "I've got an ice cream cone and you can't have it!" If the possesser didn't want to "mix it up" or have the other kid to try to come after the cone, he could easily have held his tongue.
OTOH, who said Putin is to be believed or taken at face value?
HF