John Kerry has told reporters that he is hopeful that talks with the Taliban can get "back on track" but that he was "unsure whether that was possible".
The US Secretary of State also indicated that a Taliban office in Qatar which was very recently opened, would "have to close" if the Taliban decided not to continue with the negotiations.
Official peace talks on Afghanistan between the United States and the Taliban were delayed today, amid a row about an office.
American negotiators will sit down with black turbaned men from the Taliban, at least one of whom speaks impeccable English.
Afghan president Hamid Karzai says his government will not take part in any peace talks involving the Taliban - at least for now.