Taliban officials said U.S. negotiators on Saturday agreed a draft peace deal stipulating the withdrawal of foreign forces from Afghanistan within 18 months of the agreement being signed.
The details were provided to Reuters by Taliban sources at the end of six days of talks with U.S. special peace envoy Zalmay Khalilzad in Qatar aimed at ending the United States' longest war.
They have yet to be confirmed by U.S. officials nor has either side released an official statement. Officials at the U.S. embassy in Kabul were not immediately available for comment.
Khalilzad is heading to the Afghan capital Kabul to brief President Ashraf Ghani after the longer-than expected talks, the sources and a diplomat said.
According to the Taliban sources, the hardline Islamic group offered assurances that Afghanistan will not be allowed to be used by al-Qaeda and Islamic State militants to attack the United States and its allies - a key early demand of Washington.
It is not known if a draft is acceptable to both sides has been completed, or when it might take effect.
The Taliban sources said a key provision to the deal included a ceasefire but they had yet to confirm a timeline and will only open talks with Afghan representatives once the ceasefire is implemented.
"In 18 months if the foreign forces are withdrawn and ceasefire is implemented then other aspects of the peace process can be put into action," a Taliban source said, quoting from a portion of the draft.
Other clauses include a deal over the exchange and release of prisoners from the warring sides, the removal of an international travel ban on several Taliban leaders by the United States and the prospect of an interim Afghan government after the ceasefire is struck, the Taliban sources said.
The offer to appoint an interim government in Afghanistan comes at a time when top politicians including Ghani have filed their nominations for the presidential polls in July this year. Ghani has repeatedly rejected the offer to agree to the formation of an interim government.
News of progress on a deal comes as the Taliban continue to stage nearly daily attacks against the Western-backed Afghan government and its security forces.
Despite the presence of U.S.-led foreign forces training, advising and assisting their Afghan counterparts 17 years after the U.S. led an invasion to drive them from power, the Taliban controls nearly half of Afghanistan.
The United States has some 14,000 troops in Afghanistan as part of the NATO-led mission, known as Resolute Support, as well as a U.S. counter-terrorism mission directed at groups such as Islamic State and al Qaeda.
Despite reports in December last year that the United States was considering pulling out almost half of its forces, a White House spokesman said that U.S. President Donald Trump had not issued orders to withdraw the troops. However, the administration has not denied the reports, which have also prompted fears of a fresh refugee crisis.