The latest round of talks with the Taliban - now in their second week - has been "very productive," a member of the American negotiating team has said.
The team member strenuously denied Washington sought a fixed deadline for the withdrawal of its estimated 14,000 troops from Afghanistan as part of a final peace deal.
Negotiations have had fresh momentum in recent weeks after US Secretary of State Mike Pompeo visited Afghanistan's capital Kabul at the end of last month.
At the time, he said Washington was hopeful of an agreement before September 1.
The appointment last year of Zalmay Khalilzad as a US special peace envoy began the accelerated effort to find a negotiated end to Afghanistan's war and America's longest military engagement.
Since then Khalilzad has held scores of talks with the Afghan government in Kabul and abroad with the Taliban as well as with Afghanistan's neighbours, including Pakistan which has been accused of aiding the insurgents.
The US official in Qatar's capital Doha, where the Taliban maintain a political office and talks are being held, told The Associated Press that the US "definitely did not offer" an 18-month withdrawal as part of a peace deal.
Speaking anonymously because of the sensitivity of the talks, the US negotiator was responding to a time frame Taliban officials told the AP months earlier.
The US negotiator said the deal being negotiated in Doha with the Taliban is "comprehensive and includes specifics on all four parts including a cease fire, timeline, participating in intra-Afghan negotiations and counter-terrorism assurances."
On Saturday, several prominent Afghan figures left Kabul for Doha ahead of much-anticipated all-Afghan talks to begin on Sunday. The talks are co-sponsored by Germany and Qatar, and include the Taliban.
An earlier round of intra-Afghan talks, which were to be held last April, were scuttled after the two sides could not agree on participants. The Afghan government had submitted a list of 250 people. The Taliban likened it to a wedding party.
This time the Taliban say 60 people will participate.
Attaullah Rahman Salim, the deputy head of the government's high peace council, said 64 would be sitting around the table.
The list includes former mujahedeen who fought the Soviet in the 1980s as well as former government officials, former ambassadors, civil society representatives and a smattering of women.
Participants at the table will be there as ordinary Afghans "on equal footing" and not as government representatives, said the German sponsors.
The Taliban have consistently refused to hold direct talks with President Ashraf Ghani's government calling it a puppet administration.
They have, however, readily agreed to talks with any Afghan, including from within the government, but as an ordinary Afghan.
Ghani, who has been conspicuously quiet about the upcoming intra-Afghan dialogue, has consistently demanded Taliban talk directly with the government.
