"There have to be some red lines," said Jawed Ludin, Afghanistan's deputy foreign minister for political affairs. "Some of the achievements that we've had in the last 10 years can't be negotiated."

Karzai sounded confident that most of the Taliban would acknowledge this.

"I think there is now a critical mass in Afghanistan of the educated, of the Afghan people who want a future of progress and stability," he said. "And I think also that the Taliban recognize that this corner has been turned, the majority of them. Some may be there among them who would not -- who would remain, you know, in the darkest of the mindset possible. But those are a few."