It might be argued - it is being argued - that ending the Union is a much bigger step and thus would require a binding popular verdict upon the final outcome, not simply pre-negotiation consent.
The top United Nations envoy in Afghanistan, Steffan de Mistura, said the Taliban statement was "in the opposite direction" to many other recent signals, and could be part of a pre-negotiation strategy of creating perceptions, building up pressure and increasing military attacks.
The French economy minister Laurent Fabius said that "no European" could accept such a clause, as it implies a pre-determined end-point for the negotiation.