Others have their doubts as many other insurgents who have been released by Pakistan are thought to have returned to the fight.
Dobbins said Karzai had “high hopes” for the peace process.
“I think we are a little more cautious about what the Taliban is likely to be willing to do. But we agreed that we needed to have a common plan and it needs to be a plan to be in common with Pakistan, who has offered to be helpful,” Dobbins said.
The Taliban have refused to talk directly with Karzai, his government or its representatives.
U.S.-backed talks between Afghanistan and the Taliban failed in June.
Pakistan has a complicated relationship with the Taliban.
It helped the group seize control of Afghanistan in 1996, and Kabul has repeatedly accused Islamabad of providing the insurgents sanctuary on its territory following the U.S.-led invasion of Afghanistan in 2001.
