"Talks with the Taliban have started... the talks are going on well," Karzai said, addressing a conference in Kabul.
"Also foreign forces, especially the United States, are carrying out the talks themselves." The US-led war in Afghanistan is in its 10th year and there are increasing calls for a political settlement to the conflict.
US Secretary of State Hillary Clinton earlier this year called on Taliban members to split from Al-Qaeda, renounce violence and accept the constitution so they can be reconciled to society.
The US embassy in Kabul did not immediately respond to a request for comment on Karzai's remarks.
Western officials in Kabul stress that attempts to set up contacts with the Taliban are at a very early stage and that efforts are still being made to achieve a communication channel with the Taliban's leadership.
Karzai last year set up a High Council for Peace featuring senior Afghan figures in a bid to pursue talks with the Taliban in return for them laying down their arms and accepting the constitution.
These have been rejected in public by the militants, who are leading a bloody insurgency against foreign troops and Afghan forces.