An American soldier was killed in a vehicle rollover accident in Afghanistan's western Farah province on Friday, the US Department of Defense said on Saturday.

Recent meeting between US Special Representative for Afghanistan Reconciliation Zalmay Khalilzad and Taliban leaders in Qatar failed to resolve the issue of certain prisoners which the Afghan government refuses to release, sources close to the group told 1TV on Saturday.

The United States and Qatar have discussed possiblity of co-investing in Afghan projects to consolidate peace and unlock regional prosperity.

Afghan President Ashraf Ghani is set to inaugurate two regional and international conferences on peace via video link next week, the country's foreign ministry said on Thursday.

It will be clear next week when talks with the Taliban will start, President Ashraf Ghani has said.

Despite recent progress in peace process, al Qaeda in the Indian Subcontinent (AQIS) maintains close ties to the Taliban in Afghanistan, likely for protection and training, the Pentagon said in a report.

Two people were killed while eight others were wounded in two explosions in Mazar-i-Sharif, capital of Afghanistan's northern Balkh province, on Wednesday night, police said.

The UN Secretary-General's Special Representative for Afghanistan, Deborah Lyons, on Thursday warned of spoilers who seek to derail the country's peace process.

Afghan government will reconsider its commitments on peace process if the Taliban fail to reduce violence, Second Vice President Sarwar Danish warned on Wednesday.

Police chief of Afghanistan's western Herat province was injured in an attack by militants on Wednesday, sources told 1TV.