Mofti Habibur Rahman, chief of the criminal department at Taliban's interior ministry, also said other high-level and low-ranking Taliban officials inside and outside Afghanistan would take advantage of a government amnesty offer.
"The reason is that we now have an elected and legitimate government," Rahman told reporters on Saturday after surrendering to local authorities in Khost, the southeastern province near the order with Pakistan which is a hotbed of Taliban activity.
When asked if Jalaluddin Haqani, the top Taliban commander for the southeastern region would also give himself up, Rahman said: "I cannot say this because of security reasons."
He said other Taliban officials who were prepared to join the government were living in Afghanistan, Pakistan and the United Arab Emirates.
His defection comes days after local officials in the southern province of Helmand said two senior Taliban members had surrendered under Karzai's amnesty offer.
Another Taliban commander in Helmand also surrendered this
month. The Taliban have been waging an insurgency since being overthrown by US-led forces in late 2001 for refusing to hand over al-Qaida chief Usama bin Ladin, the architect of the 11 September 2001, attacks on US cities.
The government is seeking to coax rank-and-file Taliban to
give up their fight but the amnesty offer does not include 150
of the movement's senior leaders, accused of violence or of having links with al-Qaida.