U.S. Secretary of State Hillary Clinton is due to meet in Kabul with Afghan President Hamid Karzai to discuss efforts to reconcile with the Taliban and the transition of security in the war-torn country.

Clinton arrived late Wednesday on an unannounced visit.

U.S. officials say the secretary will press for a binding strategic agreement between Afghanistan and the United States that will govern relations after 2014 when American troops are scheduled to return home.

Clinton also will preview plans for upcoming conferences on the future of Afghanistan to be held in Istanbul in November and Bonn, Germany in December.

The agenda is expected to include talks on ties between Afghanistan and neighboring Pakistan. Both U.S. and Afghan officials have accused Pakistan of supporting insurgent groups in Afghanistan, a charge Islamabad denies.

The Afghan government's peace talks with the Taliban have stalled since last month's killing of former President Burhanuddin Rabbani, who had led President Karzai's outreach to the insurgents as head of the High Peace Council.

A suicide bomber posing as a Taliban emissary killed Rabbani at his home in Kabul September 20.